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CreatorTitleDescriptionSubjectDate
1 Ailion, David Charles109Ag NMR investigation of atomic motions in the incommensurate and paraelectric phases of proustite (Ag3AsS3)109Ag NMR line shape, T1 , Hahn spin echo, and Carr-Purcell-Meiboom-Gill ~CPMG! spin-echo measurements were performed in proustite (Ag3AsS3) between 420 and 47 K in order to understand the role of atomic motions in phase transitions in a system containing an incommensurate phase. These measurements ...NMR; Atomic motion; Proustitie; Phase transitions; Line shape2000
2 Ailion, David Charles14N study of the role of N-D---O bonds in the deuteron glass transition14N spin-lattice relaxation-time measurements in Rb0.28(ND4)0.72D2PO4 provide direct evidence for the fast exchange averaging of the "long" and "short" N-D---O hydrogen bonds between the ND4 group and the four surrounding PO4 groups. This exchange and the associated distortion of the ND4 tetrahedron...NMR; Hydrogen bonds; Spin-lattice; Relaxation-time; Deuteron glass1999
3 Ailion, David Charles31P NMR spin-lattice relaxation: structural glass dynamics in Rb1-x(ND4)xD2PO4We performed 3 1P NMR measurements of the temperature-dependent spin-lattice relaxation time in several mixed single crystals of Rbi_x(ND4 ) xD2P04 [DRADP] having different ammonium concentration x (x =0.22, 0.44, 0.78) as well as in three pure single crystals (ND4)D2P04 [DADP], (NH4)H2P04 [ADP], an...NMR; Spin-lattice; Relaxation; Crystals; Glass; Spin-glass1993
4 Ailion, David Charles; Blinc, Robert35Cl spin-lattice relaxation in incommensurate bis(4-chlorophenyl)sulfoneThe 35C1 nuclear-quadrupole-resonance (NQR) spin-lattice relaxation rate in incommensurate bis(4- chlorophenyl)sulfone (BCPS) is determined by Raman processes below 60 K and by direct one-phonon processes above 60 K. The variation of the 35C1 spin-lattice relaxation rate over the incommensurate NQR...35Cl; Incommensurate bis(4-chlorophenyl)sulfone; Raman processes; NQR; Incommensurate systems1995-01
5 Saam, Brian3He spin exchange cells for magnetic resonance imagingWe present a protocol for the consistent fabrication of glass cells to provide hyperpolarized (HP) 3He for pulmonary magnetic resonance imaging. The method for producing HP 3He is spin-exchange optical pumping. The valved cells must hold of order 1 atm.L of gas at up to 15 atm pressure. Because char...3He; Spin exchange cells; Hyperpolarized 3He; Pulmonary magnetic resonance imaging; Spin-exchange optical pumping; SEOP; Glass cells2002
6 Ailion, David Charles79Br nuclear-quadrupole-resonance lineshape and Raman-induced spin-lattice relaxation in the incommensurate phase of β- ThBr4We performed 7 9Br nuclear-quadrupole-resonance (NQR) line-shape and spin-lattice relaxation time measurements in the incommensurate (D system j8-ThBr4 over the temperature range 293-2.5 K. In addition, we extended the theory of the effects of Raman processes on amplitudon and phason spin-lattice re...Spin-lattice; NQR; Raman process; Line shape; Phason gap; Incommensurate systems1989
7 Ailion, David Charles93Nb NMR in the imcommensurate and quasi-commensurate phases of barium sodium niobateNMR spectra have been measured for the quadrupole perturbed 1/2 -1/2 transition of 9 3Nb in barium sodium niobate (BSN) between 300 and 650 K. The spectra are inhomogeneously broadened in the incommensurate (/) phase between T7 = 580 K and r c = 540 K as well as in the quasicommensurate (QC) phase ...NMR; Spectra; Barium sodium niobate; Line shapes1994
8 Mattis, Daniel C.A contribution to the many-fermion problemIn this work we reexamine the many-fermion problem in arbitrary dimensions. It is shown that in two dimensions or higher, the Hamiltonian of interacting fermions can be separated into individual nonintersecting sectors labeled by the wave-vector q. Within each sector the Hamiltonian maps onto a gene...2012-01-01
9 Gondolo, PaoloAberration features in directional dark matter detectionThe motion of the Earth around the Sun causes an annual change in the mag-nitude and direction of the arrival velocity of dark matter particles on Earth, in a way analogous to aberration of stellar light. In directional detectors, aberration of weakly interacting massive particles (WIMPs) modulates ...2012-01-01
10 Wu, Yong-ShiAbsence of (1,0) supersymmetry anomaly in world-sheet gauge theories: a purely cohomological proofA purely cohomological proof is given for the absence of the (1,0) supersymmetry anomaly in gauge theories on a world sheet. In particular, it is shown that generalized cohomological approaches to anomalies in supersymmetric gauge theory, either formulated in whole superconnection space or only in t...World sheet; String theory; Superfields; Superspace1989-01
11 Symko, Orest GeorgeAbsorption at radio frequencies in superconducting Y1Ba2Cu3OyThe large magnetic-field-dependent ac absorption in superconducting Y1Ba2Cu3Oy ceramics and powders decreases slowly with increasing frequency in the range 2-16 MHz. The magnetic-field-dependent ac absorption is observed below Tc in superconducting Y1Ba2Cu3Oy ceramics, powders and twinned crystals ...Copper-octahedral oxygen perovskites; Superconducting Y1Ba 2Cu3Oy; ac absorption1989
12 Vardeny, Zeev ValentineAbsorption studies of charged excitations in α-sexithiopheneWe present photoexcitation studies of vacuum deposited neutral films of α,ω-substituted sexithiophene (α-6T) using photoinduced absorption (PA) and PAdetected magnetic resonance spectroscopy (PADMR). We find evidence for photoinduced polarons having spin 1/2, with two absorption bands at 0.80...alpha- sexithiophene; Charged excitations; Photoexcitation; Photoinduced absorption1996
13 Vardeny, Zeev ValentineAbsorption-detected magnetic-resonance studies of photoexcitations in conjugated-polymer/C60 compositesPhotoexcitations in poly[2-methoxy-5-(2'-ethyl-hexyloxy -p-phenylene vinylene] (MEH-PPV) and composites of MEH-PPV and C60 (MEH-PPV/C60) were studied by photoinduced absorption and absorptiondetected magnetic-resonance spectroscopies. We report direct evidence that the prominent triplet photoexci...Photoexcitations; Conjugated-polymer/C60 composites; Triplet photoexcitations1996-02
14 Mattis, Daniel C.Accuracy of bosonization for localized interactionsBosonization is commonly used to calculate the ground-state energy and the dynamics of simple model nonmagnetic impurities in metals. We analyze the accuracy of this procedure in the calculation of the ground-state energy of a simple, solvable, model.Fermions; Electrons; Magnetic2000
15 Symko, Orest GeorgeAcoustic approach to thermal management: miniature thermoacoustic enginesAn acoustic approach to thermal management in electronics can be efficient and it can be directly interfaced with electronic devices. It is based on two types of thermoacoustic heat engines, which are being developed for microcircuit applications. One type of device, the prime mover, converts heat t...Thermoacoustic engines; Thermal management2006
16 Symko, Orest GeorgeAdiabatic compressional cooling of He3By adiabatic compression of a two-phase mixture of liquid and solid He3, temperatures below 2.5 mK have been obtained. These are in the range expected for nuclear ordering in solid He3.He3; Adiabatic compressional cooling1969-03
17 Rogachev, AndreyAdmittance spectroscopy study of polymer diodes in small magnetic fieldsWe performed a systematic study of bipolar and unipolar organic diodes based on the p-conjugated polymer, 2-methoxy-5-(20-ethylhexyloxy) (MEH-PPV), using electronic and magneto-transport measurements with magnetic field in the range 0-180mT and admittance spectroscopy in the frequency range 1 Hz<f<1...2012-01-01
18 Williams, Clayton C.Advances in experimental technique for quantitative two dimensional dopant profiling by scanning capacitance microscopySeveral advances have been made toward the achievement of quantitative two-dimensional dopant and carrier profiling. To improve the dielectric and charge properties of the oxide-silicon interface, a method of low temperature heat treatment has been developed which produces an insulating layer with c...Doping; Scanning capacitance microscope; SCM1999
19 Gondolo, PaoloAGAPE, a microlensing search in the direction of M31: status reportThe M31 galaxy in Andromeda is the nearest large galaxy after the Small and Large Magellanic Clouds. It is a giant galaxy, roughly 2 times as large as our Milky Way, and has its own halo. As pointed by some of us [1, 2] and independantly by A. Crotts [3], M31 provides a rich field of stars to searc...AGAPE; Andromeda Gravitational Amplification Pixel Experiment; Microlensing; MACHO; Massive compact halo objects1995
20 Gondolo, PaoloAGAPE: a search for dark matter in M31 by microlensing effects on unresolved starsM 31 is a very tempting target for a microlensing search of compact objects in galactic haloes. It is the nearest large galaxy, it probably has its own dark halo, and its tilted position with respect to the line of sight provides an unmistakable signature of microlensing. However most stars of M 31...M31; AGAPE; Pixel method; Galaxy; Halo; Cosmology; Gravitational lensing1997
21 Gondolo, PaoloAGAPE: andromeda gravitational amplification pixel experimentThe aim of the AGAPE (Andromeda Gravitational Ampli_x000C_cation Pixel Experiment), experiment which has been _x000C_rst proposed in June 1992 is to examine the distribution of massive astrophysical compact halo objects ((MACHO's) which possibly are in the galactic haloes and which could account for...AGAPE; Andromeda Gravitational Amplification Pixel Experiment; Microlensing; MACHO; Massive compact halo objects1997
22 Gondolo, PaoloAGAPEROS: searching for microlensing in the LMC with the pixel method. I. Data treatment and pixel light curves productionRecent surveys monitoring millions of light curves of resolved stars in the LMC have discovered several microlensing events. Unresolved stars could however signi _x000C_cantly contribute to the microlensing rate towards the LMC. Monitoring pixels, as opposed to individual stars, should be able to ...Data analysis techniques; Halo; Galaxies; Gravitational lensing; Pixel method; Large Magellanic Cloud; LMC1999
23 Gondolo, PaoloAgapeZ1: a large amplification microlensing event or an odd variable star towards the inner bulge of M31AgapeZ1 is the brightest and the shortest duration microlensing candidate event found to date in the Agape experiment. It occurred only 4200 from the centre of M31 at RA = 0h42m41:47s and Dec = 41°16'39.1" (J2000). Our photometry shows that the half intensity duration of the event is 5.3 days and ...AgapeZ1; Galaxy; Halo; Cosmology; Gravitational lensing; M31; Pixel method1999
24 Lupton, John MarkAir-induced fluorescence bursts from single semiconductor nanocrystalsWe observe a dramatic enhancement of the fluorescence intensity from single core/shell CdSe/ZnS nanocrystals upon sudden exposure to air from an evacuated surrounding. Both the number of particles contributing to emission increases as well as the average emission intensity from a single particle, le...CdSe; ZnS; Air-induced; Fluorescence bursts2004
25 Wu, Yong-ShiAlgebraic and geometric aspects of generalized quantum dynamicsWe briefly discuss some algebraic and geometric aspects of the generalized Poisson bracket and noncommutative phase space for generalized quantum dynamics, which are analogous to properties of the classical Poisson bracket and ordinary symplectic structure.Quantum dynamics; Jacobi identity1994-06
26 Wu, Yong-ShiAlgebraic solution for a two-level atom in radiation fields and the Freeman resonancesUsing techniques of complex analysis in an algebraic approach, we solve the wave equation for a two-level atom interacting with a monochromatic light field exactly. A closed-form expression for the quasienergies is obtained, which shows that the Bloch-Siegert shift is always finite, regardless of ...Bloch-Siegert shift; Freeman resonances; Quasienergies2006-02
27 Mattis, Daniel C.; Sutherland, BillAmbiguities with the relativistic δ-function potentialIn many cases of physical interest, the 6-function potential is a very convenient approximation to more structured, and more difficult, short-ranged potentials. In relativistic theories, its use is often mandated because only a mathematical point has a relativistically invariant shape. Neverthele...Delta function; Energy states1981-09
28 Vardeny, Zeev Valentine; Gellermann, WernerAmplified resonant Raman scattering in conducting polymer thin filmsUsing picosecond pulsed laser excitation, we investigate the optical emission characteristics of poly(2,5-dioctyloxy-p-phenylenevinylene), (DOO-PPV), thin films at high excitation intensities (~1-90 MW/cm2). We observe the presence of amplified resonance Raman scattering in the emission spectra of c...Amplified resonant Raman scattering; High excitation intensities; pi-conjugated polymers1998
29 Vardeny, Zeev ValentineAmplified spontaneous emission and lasing in conducting polymers and fluorescent dyes in opals as photonic crystalsSpectral narrowing of photoluminescence (PL) and evolution of sharp emission lines upon optical excitation have been observed in opals made of SiO2 spheres infiltrated with conducting polymers such as OOPPV and MDDOPPV and also fluorescent dyes such as rhodamine 6G, NK-3483, and coumarin 120. Their ...Amplified spontaneous emission; Lasing; Fluorescent dyes1999
30 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Amplitude and phase modes in trans-polyacetylene: resonant Raman scattering and induced infrared activityThe resonant Raman scattering (RRS) from the three Ag modes of trans-polyacetylene and the charged-induced ir modes are analyzed with use of the amplitude- and phase-mode theories. It is shown that the observed phonon frequencies and the relative intensities of all modes obtained at various laser ex...Induced infrared activity; Ag modes; Amplitude modes; Phase modes; Trans-polyacetylene1987-07
31 Sokolsky, PierreAn analog light scattering experiment of hexagonal icelike particles. part I: experimental apparatus and test measurementsAn experimental apparatus to measure the scattering properties of hexagonal icelike particles in the analog manner at the helium neon laser wavelength of 0.633 mm has been designed and built. The instrument consists of an array of 36 highly sensitive and linear photodiode detectors that are positi...1999
32 Sokolsky, PierreAn analog light scattering experiment of hexagonal icelike particles. part II: experimental and theoretical resultsThe scattering properties of hexagonal icelike crystals as measured in the analog manner by the experimental apparatus described in Part I are presented. The crystals are made out of sodium fluoride (NaF), which has an index of refraction similar to that of water ice. The experimentally determined...1999
33 Mattis, Daniel C.An expanded Luttinger modelThis paper generalizes Luttinger's model by introducing curvature (d2ε (k) dk2 ≠ 0 ) into the kinetic energy. An exact solution for arbitrary interactions is still possible in principle, but it now requires disentangling the eigenvalue spectrum of an harmonic string of interacting boson fields at...2012-01-01
34 Wu, Yong-ShiAnalyzing powers for ∏±-13C scattering at T∏=100 MeVMeasurements of the analyzing power for the nC(rr±,rr±) reaction at Trr = 100 MeV have been made at TRIUMF using a polarized target consisting of 99% 1 3C enriched butanol. Data were obtained for the ground and 3.68 MeV excited states at angles from 110° to 150° in 10° steps. The data are con...1992-02
35 Gondolo, PaoloAnnual modulation of dark matter in the presence of streamsIn addition to a smooth component of weakly interacting massive particle (WIMP) dark matter in galaxies, there may be streams of material; the effects of WIMP streams on direct detection experiments is examined in this paper. The contribution to the count rate due to the stream cuts off at some char...WIMP streams; Weakly interacting massive particles; Cutoff energy; Halo models; Sagittarius dwarf galaxy; Recoil energy; Sgr stream2006-08
36 Vardeny, Zeev Valentine; Raikh, Mikhail E.Anomalous coherent backscattering of light from opal photonic crystalsWe studied coherent backscattering (CBS) of light from opal photonic crystals with incomplete band gaps. We observed a dramatic broadening of the CBS cone for incident angles close to the Bragg condition in the crystals. We modify the conventional CBS theory to incorporate Bragg attenuation resultin...Coherent backscattering; Bragg condition2001-05
37 Vardeny, Zeev ValentineAnomalous optical and ESR properties of doped polydiethynylsilanesThe optical, transport, and ESR properties of soluble conducting four-membered polydiethynylsilane heterocycles are described. The undoped one-dimensional gap is 2.0 eV in both films and solutions; no photoluminescence is observed. I2 doping induces a single absorption band at -1.05 eV in solutions...Polydiethynylsilane; Doped polydiethynylsilanes1991-09
38 Mattis, Daniel C.Anomalous skin effect in a magnetic fieldA classical and quantum mechanical derivation of cyclotron resonance in metals is given. The classical result differs slightly from that obtained by Azbel and Kaner. The quantum derivation yields the same result as the classical calculation except that in the limit of low quantum numbers or high m...Cyclotron resonance; Skin effect; Quantum transport1958-07
39 Vardeny, Zeev Valentine; Nahata, AjayAnomalous transmission through heavily doped conducting polymer films with periodic subwavelength hole arrayWe observed resonantly enhanced (or anomalous transmission) terahertz transmission through two-dimensional (2D) periodic arrays of subwavelength apertures with various periodicities fabricated on metallic organic conducting polymer films of polypyrrole heavily doped with PF6 molecules [PPy(PF6)]. Th...2006
40 Mattis, Daniel C.Anomaly in spin-wave spectrum of magnetic metalsIt is pointed out that in the band theory of magnetism the magnons have frequencies comparable to the Fermi energy. Therefore, in the calculation of the magnon spectrum of iron, nickel, cobalt, etc., it is the time- or frequency-dependent response function of the electrons which is used, and this ...Magnetic metals1966-11
41 Kieda, David B.Antarctic impulsive transient antenna (ANITA) instrumentationWe will report on the details of the ANITA instrument. This instrument is fundamentally a broadband antenna, which is arrayed and constructed in such a way as to be optimized for the detection and characterization of high-energy neutrino cascades [1]. The requirement to maximize the detector view of...ANITA; Antarctic Impulsive Transient Antenna; Neutrino; Balloon; Antarctica2003
42 Wu, Yong-ShiAnyons on a torus: braid group, Aharonov-Bohm period, and numerical studyWe present a careful construction of anyons on a torus starting with the braid-group analysis. The rules of Wen, Dagotto, and Fradkin for putting anyons on a torus are reproduced with some minor improvements. The existence of noncontractible loops leads to braid-group representations characterized n...Braid group; Magnetic flux1991-05
43 Gerton, JordanApertureless near-field fluorescence microscope for biological imagingWe measured the optical response of fluorescent beads to sharp metallic and semiconducting probes, revealing several underlying near-field interactions. Our results suggest that -10 nanometer optical resolution with spectroscopic chemical sensitivity is possible, and bear strongly on molecular-scal...2003-01-01
44 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Apparent phonon side-band modes in π-conjugated systems: polymers, oligomers and crystalsThe emission spectra of many π-conjugated polymers and oligomers contain side-band replicas with apparent frequencies that do not match the Raman active mode frequencies. Using a time dependent model we show that in such many mode systems, the increased damping of the time dependent transition dipo...2005-11
45 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Apparent vibrational side bands in rr-conjugated systems: the case of distyrylbenzeneThe photoluminescence sPLd spectra of dilute solution and single crystals of distyrylbenzene show unique temperature-dependent vibronic structures. The characteristic single frequency progression at high temperatures is modulated by a low-frequency progression series at low temperatures. None of th...pi-conjugated systems; Distyrylbenzene; Vibrational side-bands; Vibronic structures; DSB2005-02
46 Symko, Orest GeorgeApplication of SQUID magnetometer to nuclear magnetic thermometryThis paper presents an application of a SQUID magnetometer for low temperature thermometry using the magnetic properties of a nuclear paramagnet. The static magnetization of a material which obeys Curie's law provides a very sensitive means of thermometry. Also included in the device is the capabi...SQUID magnetometer; Nuclear magnetic thermometry; Low temperature thermometry1976
47 Mattis, Daniel C.Application of tridiagonalization to the many-body problemThe problem of a single magnetic, Wolff-model impurity in an otherwise ideal metallic host is investigated using the nonperturbative Lanczos method. Convergence is very rapid. The many-body ground-state energy is investigated and comparisons are made with Tomonaga operator theory and other weak-coup...Lattice; Electrons; Interaction; Ground-state energy; Tridiagonalization; Magnetic impurity; Nonmagnetic metals1983
48 Mattis, Daniel C.Application of tridiagonalization to the many-body problem. II. Finite TIn a previous paper of the same title, we obtained the ground-state energy of a magnetic (Wolff-model) impurity in a nonmagnetic metal. In the present Brief Report, we calculate the impurity's contribution to the density of states and heat capacity of the metal at low temperatures. Here, the Lancz...Ground-state energy; Tridiagonalization; Magnetic impurity; Nonmagnetic metals; Heat capacity1984-06
49 DeTar, CarletonAssorted weak matrix elements involving the bottom quarkAs part of a larger project to estimate the fB decay constant, we are recalculating fstatic B using a variational smearing method in an effort to improve accuracy. Preliminary results for the static BB parameter and HQET two point functions are also presented.Bottom quark; Decay constants; HQET; Effective field theory1997-02
50 Ailion, David Charles; Morris, Alan H.Asymmetric spin echo sequences. a simple new method for obtaining NMR 1H spectral imagesThe nuclear magnetic resonance (NMR) signal decay produced by reversible tissue-induced dephasing of the magnetization components in the transverse plane (reversible tissue-induced dephasing) was measured and expressed as a function of a new transverse relaxation time T'2 (T2 prime) for samples of ...Asymmetric spin echo; Signal decay; Chemical shift; Tissue characterization; Lung aeration; Fatty liver1985
51 Saam, BrianAsymptotic and intermediate long-time behavior of nuclear free induction decays in polycrystalline solids and powdersFree induction decay (FID) measured by nuclear magnetic resonance (NMR) in a polycrystalline solid is the isotropic average of the FIDs for individual single crystallites. It has been recently proposed theoretically and verified experimentally that the long-time behavior of single-crystal FIDs has t...2012-01-01
52 Williams, Clayton C.Atomic force microscope-force mapping and profiling on a sub 100-Å scaleA modified version of the atomic force microscope is introduced that enables a precise measurement of the force between a tip and a sample over a tip-sample distance range of 30-150Å. As an application, the force signal is used to maintain the tip-sample spacing constant, so that profiling can be ...Attractive force; Silicon wafer1987
53 Williams, Clayton C.Atomic scale trap state characterization by dynamic tunneling force microscopyDynamic tunneling force microscopy (DTFM) is applied to the study of point defects in an inter-layer dielectric film. A recent development enables simultaneous acquisition of DTFM, surface potential, and topographic images while under active height feedback control. The images show no clear correlat...2014-01-01
54 Mishchenko, EugeneAttraction-repulsion transition in the interaction of adatoms and vacancies in grapheneThe interaction of two resonant impurities in graphene has been predicted to have a long-range character with weaker repulsion when the two adatoms reside on the same sublattice and stronger attraction when they are on different sublattices. We reveal that this attraction results from a single energ...2014-01-01
55 Gondolo, PaoloAxion cold dark matter in nonstandard cosmologiesWe study the parameter space of cold dark matter axions in two cosmological scenarios with nonstandard thermal histories before big bang nucleosynthesis: the low-temperature reheating (LTR) cosmology and the kination cosmology. If the Peccei-Quinn symmetry breaks during inflation, we find more allow...2010-01-01
56 Gondolo, PaoloAxion cold dark matter in view of BICEP2 resultsThe properties of axions that constitute 100% of cold dark matter (CDM) depend on the tensor-to-scalar ratio r at the end of inflation. If r ¼ 0.20 þ0.07 −0.05 as reported by the BICEP2 Collaboration, then "half" of the CDM axion parameter space is ruled out. Namely, in the context of single-fie...2014-01-01
57 Symko, Orest GeorgeBackground signals in SQUID magnetometersSince a SQUID magnetometer is an extremely sensitive device capable of detecting minute magnetic flux changes in a sample, it will also detect unwanted signals from materials near the magnetometer. The presence of temperature dependent "background signals" limits the accuracy of measurements of ...SQUID magnetometer; Background signals1974
58 Sokolsky, PierreBackward production in π-p→pπ+π-π- at 8 GeV/c*We have studied backward baryon and meson production in π'p → pπ+pπ +π-π- at 8.0 GeV/c using a streamer chamber triggered by the detection of a fast forward proton. Our data sample (1227 events) displays prominent N*p and N*f quasi-two-body production. These states are investigated with rega...1976-01
59 Mattis, Daniel C.Band theory of ferromagnetism, antiferromagnetism, and spin wavesIntra-atomic exchange (Hund's rule mechanism) and Heisenberg nearest-neighbor exchange are examined for their role in the ferromagnetism of metals with degenerate bands. The equations of motion of spin waves valid near T=0°K are derived, and a number of branches are found. When the equations are ...Orbital degeneracy; Indirect exchange theory; Band theory1964
60 DeTar, CarletonBaryon density correlations in high temperature hadronic matterAs part of an ongoing effort to characterize the high temperature phase of QCD, in a numerical simulation using the staggered fermion scheme, we measure the quark baryon density in the vicinity of a fixed test quark at high temperature and compare it with similar measurements at low temperature and ...Baryon density; Staggered fermions; Quark plasma1994-06
61 Vardeny, Zeev ValentineBelow-gap excitation of ∏-conjugated polymer-fullerene blends: implications for bulk organic heterojunction solar cellsWe used a variety of optoelectronic techniques such as broadband fs transient and cw photomodulation spectroscopies, electroabsorption, and short-circuit photocurrent in bulk heterojunctions organic solar cells for studying the photophysics in ∏-conjugated polymer-fullerene blends with below-gap...pi-conjugated polymers; Fullerene blends; Below-gap excitations; Bulk heterojunctions; Bulk organic heterojunction solar cells; Photophysics2008-07
62 Bromley, Benjamin C.Binary disruption by massive black holes: hypervelocity stars, S stars, and tidal disruption eventsWe examine whether disrupted binary stars can fuel black hole growth. In this mechanism, tidal disruption produces a single hypervelocity star (HVS) ejected at high velocity and a former companion star bound to the black hole. After a cluster of bound stars forms, orbital diffusion allows the black ...2012-01-01
63 Mattis, Daniel C.Bond asymmetry and high-Tc superconductivityWe propose a simple mechanism, anchored in weak-coupling BCS theory, which ties together the following facts: high Tc; quasi two dimensionality; orthorhombic distortion and/or disordered lines of oxygen; proximity to a metal-insulator transition; and anomalously small isotope effects.Distortion; Singularity; Oxygen1987
64 Wu, Yong-ShiBosonization of one-dimensional exclusons and characterization of Luttinger liquidsWe achieve a bosonization of one-dimensional ideal gas of particles obeying exclusion statistics A (so called A exclusons) at low temperatures, resulting in a new variant of c = 1 conformal field theory with compactified radius R = √1/λ. These ideal excluson gases exactly reproduce the low-7 crit...Bosonization; Exclusons; Ideal gas; Luttinger liquids1995-07
65 Mattis, Daniel C.Bound exciton and hole: an exactly solvable three-body model in any number of dimensionsA three-body problem, concerning two holes in a nondegenerate valence band and a single electron in a conduction band, with strong short-range interactions, is solved exactly in any number of dimensions. The binding depends nontrivially on the ratio of the valence to conduction bandwidths (i.e., on ...Three-body problem; Trion; Bond energies1982-09
66 Wu, Yong-ShiBPS R-balls in N = 4 SYM on R × S3, quantum Hall analogy and AdS/CFT holographyIn this paper, we propose a new approach to study the BPS dynamics in N = 4 supersymmetric U(N) Yang-Mills theory on R × S3, in order to better understand the emergence of gravity in the gauge theory. Our approach is based on supersymmetric, space-filling Q-balls with R-charge, which we call R-ball...2006-06-01
67 Lupton, John MarkBragg scattering from periodically microstructured light emitting diodesWe present a simple method of generating a periodic wavelength scale structure in the optically active layer of a light emitting diode. This is achieved by solution deposition of a light emitting polymer on top of a corrugated substrate. The periodic structure allows waveguide modes normally trapped...Bragg scattering; Periodic wavelength scale structure2000
68 Wu, Yong-ShiBraid group and anyons on a cylinderIn this paper we present a careful reexamination of anyons on a cylinder (or annulus), starting from the braid-group analysis. Proper attention is paid to the topological features arising from the existence of noncontractible loops. The rule for putting anyons on a square lattice has to be modified ...Braid group; Annulus1991-02
69 Wu, Yong-ShiBraid group, gauge invariance, and topological orderTopological order in two-dimensional systems is studied by combining the braid group formalism with a gauge invariance analysis. We show that flux insertions (or large gauge transformations) pertinent to the toroidal topology induce automorphisms of the braid group, giving rise to a unified algebrai...Braid group; Topological order; Zero temperature; Two-dimensional systems2006-07
70 Wu, Yong-ShiBrane creation in M(atrix) theoryWe discuss, in the context of M(atrix) theory, the creation of a membrane suspended between two longitudinal five-branes when they cross each other. It is shown that the membrane creation is closely related to the degrees of freedom in the off-diagonal blocks which are related via dualities to the ...1998-02
71 Mishchenko, EugeneBreached superfluidity via p-wave couplingAnisotropic pairing between fermion species with different Fermi momenta opens two-dimensional areas of gapless excitations, thus producing a spatially homogeneous state with coexisting superfluid and normal fluids. This breached pairing state is stable and robust for arbitrarily small mismatch and ...Spin-orbit coupling; Gapless excitations; Cooper instability2005-03
72 Lupton, John MarkBright electroluminescence from a conjugated dendrimerPhotoluminescence and electroluminescence (EL) from a conjugated dendrimer consisting of three distyrylbenzene units linked by a central nitrogen atom as core and meta-linked biphenyl units as dendrons were investigated. The conjugated dendrimer emits green light and shows photoluminescence quantum ...Conjugated dendrimer2002
73 DeTar, CarletonB̄→D*ℓν̄ form factor at zero recoil from three-flavor lattice QCD: a model independent determination of [Vcb]We present the first lattice QCD calculation of the form factor for B→ D* lv with three flavors of sea quarks. We use an improved staggered action for the light valence and sea quarks (the MILC configurations), and the Fermilab action for the heavy quarks. The form factor is computed at zero recoi...Staggered quarks2009-01
74 DeTar, CarletonB→πlν semileptonic form factor from three-flavor lattice QCD: a model-independent determination of [Vub]We calculate the form factor f+(q2) for B-meson semileptonic decay in unquenched lattice QCD with 2 + 1 flavors of light sea quarks. We use Asqtad-improved staggered light quarks and a Fermilab bottom quark on gauge configurations generated by the MILC Collaboration. We simulate with several light...Semileptonic decay2009-03
75 Wu, Yong-ShiC-functions of noncommutative Yang-Mills theory from holographyIn this paper we study non-commutative Yang-Mills theory (NCYM) through its gravity dual. First it is shown that the gravity dual of an NCYM with self-dual θ-parameters has a Lagrangian in the form of five-dimensional dilatonic gravity. Then we use the de-Boer-Verlinde-Verlinde formalism for holog...2000-05-01
76 Symko, Orest GeorgeCalibration of SQUID magnetometer for dilute alloy studiesA SQUID magnetometer used in the study of dilute magnetic alloys or other weak magnetic systems can be calibrated by using the nuclear paramagnetism of aluminum metal. This material is useful as a calibration standard since magnetic impurities such as Fe and Mn form no local moment. This calibration...SQUID magnetometer1979
77 Gondolo, PaoloCan WIMP spin dependent couplings explain DAMA data, in light of null results from other experiments?We examine whether the annual modulation found by the DAMA dark matter experiment can be explained by Weakly Interacting Massive Particles (WIMPs), in light of new null results from other experiments. CDMS II has already ruled out most WIMP-nucleus spin-independent couplings as an explanation for DA...WIMP; Weakly interacting massive particles; DAMA; CDMS II; Parameter space2004-12
78 Dawson, KyleCCD testing and characterization for dark energy surveyA description of the plans and infrastructure developed for CCD testing and characterization for the DES focal plane detectors is presented. Examples of the results obtained are shown and discussed in the context of the device requirements for the survey instrument.DES2006
79 Symko, Orest GeorgeChaos in long Josephson junctions without external rf driving forceSimulations of long Josephson junctions in an external magnetic field show a variety of chaotic behaviors. They consist of period-doubling bifurcation, intermittency between and within Fiske steps, and quasiperiodic motion at Fiske steps. A physical explanation for the chaotic behavior is presented....Fiske steps; Chaos; Chaotic behaviors1990-09
80 Symko, Orest GeorgeCharacteristics of YBaCuO magnetic shieldsMagnetic shielding properties of YBaCuO tubes have been studied at temperatures of 77 K and 4 K. Shielding effectiveness was determined by measuring the magnetic field inside the tube in the presence of external magnetic fields. A high degree of shielding was achieved up to a critical external fie...YBaCuO magnetic shields; SQUID1991-03
81 Wu, Yong-ShiCharacterization of one-dimensional Luttinger liquids in terms of fractional exclusion statisticsWe develop a bosonization approach to study the low temperature properties of one-dimensional gas of particles obeying fractional exclusion statistics (FES). It is shown that such ideal gas reproduces the low-energy excitations and asymptotic exponents of a one-component Luttinger liquid (with no in...2001-06
82 Stringfellow, Gerald B.;Inglefield, Colin E.;Taylor, P. CraigCharacterization of unicompositional GaInP2 ordering heterostructures grown by variation of V/III ratioPhotoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies are employed to investigate single heterostructures based on two GaInP2 layers that have the same composition but different degrees of order on the cation sublattice. Four sample configurations are studied: two complemen...Heterostructures; Growth parameters; Growth temperature1997
83 Mishchenko, EugeneCharge response function and a novel plasmon mode in graphenePolarizability of noninteracting 2D Dirac electrons has a 1 1 / √qv-ω singularity at the boundary of electron-hole excitations. The screening of this singularity by long-range electron-electron interactions is usually treated within the random phase approximation. The latter is exact only in the ...Excitons; Random phase approximation2008-04
84 DeTar, CarletonCharmed-meson decay constants in three-flavor lattice QCDWe present the first lattice QCD calculation with realistic sea quark content of the D+-meson decay constant fD+. We use the MILC Collaboration's publicly available ensembles of lattice gauge fields, which have a quark sea with two flavors (up and down) much lighter than a third (strange). We obtain...Flavor physics; Charmed meson; Staggered fermions2005-09
85 Wu, Yong-ShiChiral bosonization and local Lorentz-invariant actions for chiral bosonsWe formulate a geometrical theory of self-dual scalar fields in two dimensions with a local Lorentz-invariant action. Path-integral quantization is used to derive chiral bosonization by demonstrating equivalence of correlation functions of currents and energy-momentum tensors in our theory with thos...Bosonization; String theory; Weyl fermions1988-06
86 DeTar, CarletonChiral logs with staggered fermionsWe compute chiral logarithms in the presence of "taste" symmetry breaking of staggered fermions. The lagrangian of Lee and Sharpe is generalized and then used to calculate the logs in π and K masses. We correct an error in Ref. [1]; the issue turns out to have implications for the comparison with ...Staggered fermions; Chiral logs2003-05
87 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Classification of disorder and extrinsic order in polymers by resonant Raman scatteringResonant Raman scattering is used to quantify the effect of disorder and extrinsic order on Peierls systems such as (CH)X . We introduce "X plots" in which the phonon and gap distribution are related and characterize the system by the functional dependence of the gap 2 A on the coupling X. For c/s-r...Peierls systems1985-01
88 Gondolo, PaoloClumpy neutralino dark matterWe investigate the possibility to detect neutralino dark matter in a scenario in which the galactic dark halo is clumpy. We find that under customary assumptions on various astrophysical parameters, the antiproton and continuum γ-ray signals from neutralino annihilation in the halo put the strong...Neutralinos; Clumpiness1999-01
89 Vardeny, Zeev ValentineCoherent phonon generation and detection by picosecond light pulsesUsing the picosecond pump and probe technique we have detected oscillations of photoinduced transmission and reflection in thin films of α-As2Te3 and cis-polyacetylene. These oscillations are due to the generation and propagation of coherent acoustic phonons in the film. We discuss the generation ...a-As2Te3; Cis-polyacetylene; Pump and probe technique1984-09
90 Vardeny, Zeev Valentine; Raikh, Mikhail E.Coherent random lasing: trapping of light by the disorderRecent discovery of the coherent lasing from various disordered materials adds a new dimension to the conventional physics of light propagation in multiply scattering media. It suggests that in the situation, when the propagation of light is diffusive on average, the coherent feedback can be provid...Coherent random lasing; Coherent lasing; Disorder; Disordered materials; Random lasers; Random resonators; Power Fourier transform; Light propagation2004
91 Vardeny, Zeev ValentineCoherent umklapp scattering of light from disordered photonic crystalsA theoretical study of the coherent light scattering from disordered photonic crystals is presented. In addition to the conventional enhancement of the reflected light intensity into the backscattering direction, the so-called coherent backscattering (CBS), the periodic modulation of the dielectri...Coherent umklapp scattering; Disordered photonic crystals; Coherent backscattering; Bragg2001-05
92 Ailion, David CharlesCommensurability and defect-induced phason gaps in incommensurate systemsThe phason energy gap has been observed to increase on going from the incommensurate to higher-order commensurate phases in the "devil's staircase" compound [N(CH3)4]2ZnCl4. The gap was determined via the phason-induced 1 4N spin-lattice relaxation contribution, which was obtained from the variati...Phasons; Commensurate; Incommensurate; Lattices; Modulation1985
93 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Comment on "Frequency response and origin of the spin-½ photoluminescence-detected magnetic resonance in a ∏-conjugated polymerIn a recent paper, Segal et al. [Phys. Rev. B 71, 245201 (2005)] advanced a new explanation for the dynamics of spin-1/2 photoluminescence-detected magnetic resonance (PLDMR) in films of a rr-conjugated polymer, namely, a soluble derivative of poly(phenylene-vinylene) (MEH-PPV), using a model [dubbe...Photoluminescence-detected magnetic resonance; PLDMR; pi-conjugated polymers; Poly(phenylene-vinylene); MEH-PPV2007-06
94 Mattis, Daniel C.Comment on "Ground-state properties of a spin-1 antiferromagnetic chainBotet and Jullien [Phys. Rev. B 27, 613 (1983)] and Botet, Jullien, and Kolb [Phys. Rev. B 28, 3914 (1983)] performed a finite-size scaling analysis of the spin-1 antiferromagnetic Heisenberg-Ising chain. Their work was criticized by Bonner and Mtiller [Phys. Rev. B 29, 5216 (1984)] on the grounds...Antiferromagnets; Ground-state; Ising chain; Energy gap1985-04
95 Vardeny, Zeev ValentineComment on "Large optical nonlinearity of semiconducting single-walled carbon nanotubes under resonant excitations"In a recent Letter Maeda et al. studied the optical nonlinearities of single-walled carbon nanotubes (SWNT) films using both ??Z-scan?? and ??pump and probe?? (PP) techniques with ~100 fs time resolution [1]. They found that SWNTs have a large resonant third-order nonlinear optical susceptibili...SWNT; Coherent artifact2006
96 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Comment on "Yield of singlet excitons in organic light-emitting devices: a double modulation photoluminescence-detected magnetic resonance study"In a recent Letter [1] Lee et al. studied the spin 1/2 photoluminescence-detected magnetic resonance (PLDMR) of a soluble derivative of poly-phenylene vinylene [MEH-PPV] using a double modulation scheme, where both the laser excitation intensity and the microwave power were modulated at ?ex and ?...Singlet excitons; PLDMR; Poly-phenylene vinylene; MEH-PPV; Quenching; Spin dependent recombination; OLED2006
97 Saam, BrianComment on pressure dependence of wall relaxation in polarized 3He gaseous cellsZheng et al. [Zheng, Gao, Ye, and Zhang, Phys. Rev. A 83, 061401(R) (2011)] have measured a strong linear pressure dependence of the nuclear relaxation rate of 3He in glass cells typically used to generate and/or store polarized 3He at room and cryogenic temperatures. Their interpretation is that th...2012-01-01
98 Saam, BrianComment on: New limit on lorentz-invariance- and CPT-violating neutron spin interactions using a free-spin-precession 3He- 129Xe comagnetometerIn Ref. [1], the authors use a classical result for the magnetic field created by a uniform magnetization to analyze the effects of magnetic interactions between 3He and 129Xe nuclear spins. We point out that the classical result is not applicable for interaction between nuclear spins: the actual in...2014-01-01
99 Sokolsky, PierreComparison of air fluorescence and ionization measurements of E.M. shower depth profiles: test of a UHECR detector techniqueMeasurements are reported on the fluorescence of air as a function of depth in electromagnetic showers initiated by bunches of 28.5 GeV electrons. The light yield is compared with the expected and observed depth profiles of ionization in the showers. It validates the use of atmospheric fluorescence...Air fluorescence; Electromagnetic shower; Ultra-high energy cosmic rays; Ionization2006-02
100 Gondolo, PaoloCompatibility of DAMA dark matter detection with other searchesWe present two examples of velocity distributions for light dark matter particles that reconcile the annual modulation signal observed by DAMA with all other negative results from dark matter searches. They are: (1) a conventional Maxwellian distribution for particle masses around 5 to 9 GeV; (2) ...DAMA; CDMS; Neutralinos; WIMP; Weakly interacting massive particles; Halo models; Dark matter stream2005-06
101 Mattis, Daniel C.Conductivity of one-dimensional interacting fermions*Using an exactly soluble model, the decay rate of a current-carrying state of one-dimensional fermions is calculated in the presence of random scatterers at finite temperature and the dc conductivity thereby inferred. For interacting fermions it is modified by a factor (T/T + θ)g, where g is a posi...Fermi gas1974-04
102 Vardeny, Zeev ValentineConfined and delocalized polarons in ∏-conjugated oligomers and polymers: a study of the effective conjugation lengthWe studied optical absorption of polarons in ∏-conjugated oligomers and polymers using the photoinduced absorption technique as well as chemical doping spectra from the literature. We find that the photon energy of the polaron low-energy transition obeys a relationship that depends only on the oli...Confined polarons; Delocalized polarons; pi-conjugated oligomers; pi-conjugated polymers; Effective conjugation length2004-06
103 DeTar, CarletonConjecture concerning the modes of excitation of the quark-gluon plasmaIt is a widely held belief that at temperatures much higher than the confinement scale of quantumchromodynamics (QCD), quarks and gluons become free, giving rise to a new form of matter, called the quark-gluon plasma. It is conjectured here that the characterization of the plasma as a free or weakl...Polyakov loops; Excitation1985-07
104 Vardeny, Zeev ValentineConjugation-length dependence of spin-dependent excition formations rates in ∏-conjugated oligomers and polymersWe have measured the ratio, r =ơ s/ơT of the formation cross section, ơ of singlet and triplet excitons from polarons in ∏-conjugated oligomer and polymer films, using a spectroscopic technique we developed recently. We discovered a universal relation between r and the conjugation length (CL): ...pi-conjugated polymers; Conjugation length; Polaron recombination2002-04
105 Symko, Orest GeorgeContinuously operating 4He evaporation refrigeratorA simple and compact device was developed to provide continuous, self-regulating refrigeration at approximately 1.3 K. The temperature of the device remains nearly constant, independent of external power, up to a critical power. For a molar flow rate of 10^-4 moles/sec, the refrigerator can absorb...4He evaporation refrigerator1971
106 DeTar, CarletonContinuum limit in the quenched approximationPrevious work at G/g2 = 5.7 with quenched staggered quarks is extended with new calculations at 5.85 and 6.15 on lattices up to 323 x 64. These calculations allow a more detailed study of extrapolation in quark mass, finite volume and lattice spacing than has heretofore been possible. We discuss h...Decay constants; Staggered quarks; Wilson quarks1996-03
107 DeTar, CarletonContinuum limit of lattice QCD with staggered quarks in the quenched approximation: a critical role for the chiral extrapolationWe calculate the light quark spectrum of lattice QCD in the quenched approximation using staggered quarks. We take the light quark mass, infinite volume, continuum limit. With nonlinear chiral extrapolations, we find that the nucleon to p mass ratio is mN/mp =­ 1.254 + 0.018 + 0.028, where the err...Staggered quarks; Chiral extrapolations1998-10
108 Lupton, John MarkControl of mobility in molecular organic semiconductors by dendrimer generationConjugated dendrimers are of interest as novel materials for light-emitting diodes. They consist of a luminescent chromophore at the core with highly branched conjugated dendron sidegroups. In these materials, light emission occurs from the core and is independent of generation. The dendron branchin...Dendrimer generation; Dendron branching; Charge transport; Mobility2001-03
109 Vardeny, Zeev ValentineCooperative and stimulated emission in poly(p-phenylene-vinylene) thin films and solutionsWe discuss cooperative and stimulated emissions and separate their respective contributions to the emission spectral narrowing in thin films and solutions of poly(p-phenylene-vinylene) derivatives. Whereas cooperative radiation is favored in films with poor optical confinement, directional stimula...pi-conjugated polymers; PPV; Spectral narrowing1998-04
110 Vardeny, Zeev Valentine; Raikh, Mikhail E.Cooperative emission from a disordered system: a classical modelThe effect of disorder on the collective emission from a system of classical oscillators is studied theoretically. Three types of disorder are considered: random orientation of dipole moments, finite spread in frequencies of the individual oscillators (diagonal disorder), and dipole-dipole interacti...Cooperative emission; Disordered system; Dipole-dipole interaction; Oscillators1997
111 Vardeny, Zeev ValentineCooperative emission in ∏-conjugated polymer thin filmsPicosecond dynamics of exciton emission and absorption have been studied in neat thin films of a variety of poly (phenylene vinylene) derivatives. We found that the stimulated emission band of 120 nm width and ~1 ns duration, which is observed at low exciton density n, collapses at n > 1017 cm-3 int...Pi-conjugated polymers; Poly (phenylene vinylene) derivatives; PPV derivatives; Cooperative emission1997-01
112 Gondolo, PaoloCosmic ray positron excess and neutralino dark matterUsing a new instrument, the HEAT Collaboration has confirmed the excess of cosmic ray positrons that they first detected in 1994. We explore the possibility that this excess is due to the annihilation of neutralino dark matter in the galactic halo. We confirm that neutralino annihilation can produ...Neutralinos; Supersymmetric models; Positron flux; Annihilations2002-02
113 Kieda, David B.; Gaisser, Thomas K.; Sokolsky, PierreCosmic-ray composition around 10^18 eVWe use the depth of maximum distribution as measured by the stereo Fly's Eye detector to study the chemical composition of the primary cosmic radiation between 3x 1017 eV and 1019 eV. The analysis depends on the use of simulations to study the response of the detector as well as sensitivity to assum...Fly's Eye; Cosmic ray composition; Cosmic ray nuclei; Chemical composition1993-03
114 Sokolsky, PierreCosmic-ray composition around 10^18 eVWe use the depth of maximum distribution as measured by the stereo Fly's Eye detector to study the chemical composition of the primary cosmic radiation between 3 x 10^17 eV and 10^19 eV. The analysis depends on the use of simulations to study the response of the detector as well as sensitivity to as...Energy spectrum; Extensive air showers; Inelasticity; Hadronic interactions1993-03
115 Mishchenko, EugeneCoulomb drag by small momentum transfer between quantum wiresWe demonstrate that in a wide range of temperatures Coulomb drag between two weakly coupled quantum wires is dominated by processes with a small interwire momentum transfer. Such processes, not accounted for in the conventional Luttinger liquid theory, cause drag only because the electron dispersion...Coulomb drag; Quantum wires; Luttinger liquid2003-09
116 DeTar, CarletonCritical behavior at the chiral phase transitionIt is generally expected that two-flavor QCD undergoes a high temperature chiral symmetry restoring phase transition at zero quark mass, with O(4) critical behavior[1]. Verifying this expectation is important for understanding the phenomenology of the transition and for facilitating an extrapolation...Phase transitions; Staggered fermions1998-04
117 DeTar, CarletonCritical behavior in Nt=4 staggered fermion thermodynamicsQuantum chromodynamics with two zero mass flavors is expected to exhibit a phase transition with O(4) critical behavior. Fixing the universality class is important for phenomenology and for facilitating the extrapolation of simulation data to physical quark mass values. Other groups have reported r...Staggered fermions; Phase transitions2000-01
118 DeTar, CarletonCritical behavior in Nt=4 staggered fermion thermodynamicsQuantum chromodynamics with two zero mass flavors is expected to exhibit a phase transition with O(4) critical behavior. Fixing the universality class is important for phenomenology and for facilitating the extrapolation of simulation data to physical quark mass values. Other groups have reported r...Staggered fermions; Phase transitions; Quark-gluon plasma; Chiral symmetry2000-01
119 Mattis, Daniel C.Critical curves and thermodynamic phases of lattice fluids and antiferromagnets with structured interactionsWe study the classical lattice gas with hard cores, nearest-neighbor repulsive forces, and next-nearest-neighbor attractive forces. We find several thermodynamic phases (vapor, liquid, and solid) and unusually shaped critical curves, yet no critical point or triple point. We find and discuss discont...Ising antiferromagnet; Molecular field theory1971-06
120 Vardeny, Zeev ValentineCylindrical micolasers and light emitting devices from conducting polymersSubstantially improved, photopumped polymer lasers are demonstrated using microrings and microdisks of various diameters D ranging from 5 to 200 mm. Various cavity-dependent laser modes were observed, which for D,10 mm were dominated by a single longitudinal mode with linewidth of less than 1 Å. Th...Cylindrical micolasers; OLED; Photopumped polymer lasers; Microrings; Microdisks; Microlasers1998
121 Gondolo, PaoloDaily modulation due to channeling in direct dark matter crystalline detectorsThe channeling of the ion recoiling after a collision with a weakly interacting massive particle (WIMP) in direct dark matter crystalline detectors produces a larger scintillation or ionization signal than otherwise expected. Channeling is a directional effect, which depends on the velocity distrib...2011
122 Gondolo, PaoloDark matter and relic particlesFor the first time, we have a believable inventory of the contents of the universe. First, we have compelling evidence that the universe is flat (or at least very nearly so), consistent with the prediction of inflation. Measurements of the first acoustic peak in the angular power spectrum of the Cos...Relic particles; MACHOs; WIMP; Weakly interacting massive particles2001
123 Gondolo, PaoloDark matter and the first stars: a new phase of stellar evolutionA mechanism is identified whereby dark matter (DM) in protostellar halos dramatically alters the current theoretical framework for the formation of the first stars. Heat from neutralino DM annihilation is shown to overwhelm any cooling mechanism, consequently impeding the star formation process and ...Dark stars2008-02
124 Gondolo, PaoloDark matter annihilation at the galactic centerCold dark matter near the galactic center is accreted by the central black hole into a dense spike. Particle dark matter annihilation makes the spike a compact source of photons, electrons, positrons, protons, antiprotons, and neutrinos. The spike luminosity depends on the halo density profile: halo...Neutralinos; Neutrino flux1999-08
125 Gondolo, PaoloDark matter axions revisitedWe study for what specific values of the theoretical parameters the axion can form the totality of cold dark matter. We examine the allowed axion parameter region in the light of recent data collected by the WMAP5 mission plus baryon acoustic oscillations and supernovae, and assume an inflationary...WMAP5 mission; PQ symmetry; Anharmonicity; Misalignment angle2009-08
126 Gondolo, PaoloDark matter in the MSSM golden regionDark matter is examined within the ‘‘golden region'' of the minimal supersymmetric standard model. This region satisfies experimental constraints, including a lower bound on the Higgs mass of 114 GeV, and minimizes fine-tuning of the Z boson mass. Here we impose additional constraints (particula...MSSM golden region; Neutralinos; Higgs mass2009-02
127 Gondolo, PaoloDark stars: BegynnelsenThe first phase of stellar evolution in the history of the universe may be Dark Stars, powered by dark matter heating rather than by fusion. Weakly interacting massive particles, which are their own antiparticles, can annihilate and provide an important heat source for the first stars in the univers...Dark stars; WIMP; Weakly interacting massive particles; Annihilations2009
128 Gondolo, PaoloDark stars: dark matter in the first stars leads to a new phase of stellar evolutionThe _x000C_first phase of stellar evolution in the history of the universe may be Dark Stars, powered by dark matter heating rather than by fusion. Weakly interacting massive particles, which are their own antiparticles, can annihilate and provide an important heat source for the fi_x000C_rst stars...Dark stars; WIMP; Weakly interacting massive particles2008-06
129 Gondolo, PaoloDark Stars: Död och ÅteruppståndelseThe first phase of stellar evolution in the history of the universe may be Dark Stars, powered by dark matter heating rather than by fusion. Weakly interacting massive particles, which are their own antiparticles, can annihilate and provide an important heat source for the first stars in the univers...Dark stars; WIMP; Weakly interacting massive particles2009
130 Gondolo, PaoloDark Stars: the first stars in the universe may be powered by dark matter healingA new line of research on Dark Stars is reviewed, which suggests that the first stars to exist in the universe were powered by dark matter heating rather than by fusion. Weakly Interacting Massive Particles, which may be there own antipartmers, collect inside the first stars and annihilate to produc...Dark stars; WIMP; Weakly interacting massive particles2009
131 Mattis, Daniel C.Decay of electron waves in a random mediumThis paper reports calculation of the time-correlation function of an electron wave of given wave vector k in a three-dimensional medium with weak scatterers randomly distributed. An initial parabolic decay is followed by the usual exponential law which, asymptotically, gives way to a 1/t3 law.Scattering; Potential; Coupling1982
132 Wu, Yong-ShiDeformed Hubbard operator, bosonization, and phase diagram of the one-dimensional t-J modelWe present an analytic study of the phase diagram of the one-dimensional t-J model and a couple of its cousins. To deal with the interactions induced by the no double occupancy constraints, we introduce a deformation of the Hubbard operators. When the deformation parameter ∆ is small, the induced...Hubbard operator; Bosonization; Deformation; t-J model2002-10
133 Kieda, David B.Deployment of a pair of 3M telescopes in UtahTwo 3m telescopes are being installed in Grantsville Utah. They are intended for the testing of various approaches to the implementation of intensity interferometry using Cherenkov Telescopes in large arrays as receivers as well as for the testing of novel technology cameras and electronics for grou...Star Base Utah; 3M telescopes; Intensity interferometry; Cherenkov telescopes2008
134 Williams, Clayton C.Depth dependent carrier density profile by scanning capacitance microscopyThe depth dependent carrier density was measured on an arsenic implanted silicon sample using scanning capacitance microscopy (SCM). The capacitance versus voltage scan was performed by applying dc biases with a dither ac signal. A strong dc bias dependence was observed at the interface of an abru...Carrier density; Silicon submicrometer technology; Scanning capacitance microscopy1997
135 Williams, Clayton C.Depth dependent carrier density profile by scanning capacitance microscopyThe depth dependent carrier density was measured on an arsenic implanted silicon sample using scanning capacitance microscopy (SCM). The capacitance versus voltage scan was performed by applying dc biases with a dither ac signal. A strong dc bias dependence was observed at the interface of an abru...Carrier density; Silicon submicrometer technology; Scanning capacitance microscopy1997
136 Gondolo, PaoloDetectability of the Sgr dwarf leading tidal stream with Auger, EUSO, or OWLWe point out that if heavy metastable particles composing the dark matter of our galaxy are responsible for the ultrahigh energy cosmic rays (UHECR) then the leading tidal stream of the Sagittarius dwarf galaxy could be detected through UHECR. The signal would be an anisotropy in the UHECR flux sma...Sagittarius dwarf galaxy; Sgr stream; anisotropy2004-07
137 Gondolo, PaoloDetectability of weakly interacting massive particles in the Sagittarius dwarf tidal streamTidal streams of the Sagittarius dwarf spheroidal galaxy (Sgr) may be showering dark matter onto the solar system and contributing ~(0:3-23)% of the local density of our galactic halo. If the Sagittarius galaxy contains dark matter in the form of weakly interacting massive particles (WIMPs), the ext...WIMP; Weakly interacting massive particles; Sagittarius dwarf galaxy; Recoil energy; Sgr stream2005-02
138 Vardeny, Zeev ValentineDetection of electronic excited states in conjugated polymers by picosecond transient strain spectroscopyWe describe a new type of spectroscopy based on picosecond transient strain in absorption photomodulation that can be used to detect and identify both allowed and forbidden optical transitions in solid thin films. We have applied the new spectroscopy to a variety of conducting polymer films such as ...Picosecond transient strain spectroscopy1995-02
139 Ailion, David CharlesDetection of slow modulation wave diffusion in incommensurate barium sodium niobate by 93Nb 2D exchange NMR93Nb two-dimensional (2D) exchange NMR was used to study ultraslow motions in incommensurate barium sodium niobate (BSN) in the temperature range 500 - 560 K. These 2D exchange data provide strong evidence for diffusionlike motion of the modulation wave in BSN. Such motions in BSN had been previousl...NMR; Hahn spin-echo decay; Incommensurate systems.2001
140 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Detection of soliton shape modes in polyacetyleneWe observed soliton shape modes by photoinduced absorption in partially isomerized (CH)x and (CD)x, coexisting with the soliton translational modes. The shape modes' ir activity, their dependence on the degree of isomerization, and the photoinduced spectra are explained in detail by a symmetry-break...Soliton shape modes; Polyacetylene; Photoinduced absorption1986-12
141 Ailion, David Charles; Morris, Alan H.Determination of lung water content and distribution by nuclear magnetic resonance imagingNMR imaging techniques are applicable to the assessment of lung water content and distribution because the NMR signal is, under certain conditions, proportional to tissue proton density. NMR imaging is noninvasive, easily repeatable, free from ionizing radiation, and particularly suitable for the as...Water content1986
142 Rogachev, AndreyDetermination of the superconductor-insulator phase diagram for one-dimensional wiresWe establish the superconductor-insulator phase diagram for quasi-one-dimensional wires by measuring a large set of MoGe nanowires. This diagram is roughly consistent with the Chakravarty-Schmid-Bulgadaev phase boundary, namely, with the critical resistance being equal to RQ ¼ h=4e2. Deviations fr...One-dimensional wires; Superconductor-insulator phase diagram; MoGe; Chakravarty-Schmid-Bulgadaev; Phase boundary2008-11
143 Lupton, John MarkDevice model for polymer light emitting diodes: effect of temperature and oxidationWe present a temperature-dependent single carrier device model for polymer light-emitting diodes. The model includes both the injection of charge carriers over a barrier and the transport of charges across the device. To test the model, the temperature dependence of an LED based on the conjugated po...Single carrier; Temperature dependent; Poly(phenylene vinylene); Transport measurements; ITO; Disorder1999
144 Rogachev, AndreyDichotomy in short superconducting nanowires: thermal phase slippage vs. Coulomb blockadeQuasi-one-dimensional superconductors or nanowires exhibit a transition into a nonsuperconducting regime, as their diameter shrinks. We present measurements on ultrashort nanowires (∼40-190 nm long) in the vicinity of this quantum transition. Properties of all wires in the superconducting phase, e...Thermal phase slippage; Coulomb blockade2006-11-01
145 Boehme, ChristophDiffusion of hydrogen and deuterium in stack systems of SixNyHz/SixNyDz and crystalline SiH/D-, N-H/D- and Si-H/D-bond density changes were investigated in stacks consisting of a Cz-Si substrate, a thin layer of SiC>2, amorphous deuterated silicon nitride as well as amorphous hydrogenated silicon nitride in order to see if the post deposition anneal of a-SixNyHz layers on crystalline sil...Hydrogenated silicon nitride; Anneal process2000
146 Wu, Yong-ShiDiophantine equation for the three-dimensional quantum Hall effectWhen the Fermi level lies in a gap, the Hall conductivity of three-dimensional electrons in a periodic potential is expressed in a topologically invariant form with a set of three integers. If the magnetic fluxes through the three independent areas of the periodic lattice are rational numbers, one...Hall conductivity; Periodic potentials1992-06
147 Gerton, JordanDipolar relaxation collisions in magnetically trapped 7LiWe report the measurement of the rate constant for dipolar relaxation from the (F=2, mF=2) hyperfine state of 7Li. The atoms are confined in a permanent magnet trap at a field of 10^3 G. The measured value of (1.05±0.10)X10^-14 cm3/s agrees well with theory. Additionally, we determine an upper bo...1999-02
148 Williams, Clayton C.; Huang, YufengDirect comparison of cross-sectional scanning capacitance microscope dopant profile and vertical secondary ion-mass spectroscopy profileThe scanning capacitance microscope (SCM) has been shown to be useful for quantitative 2D dopant profiling near the surface of silicon. An atomic force microscope is used to position a nanometer scale tip at a silicon surface, and local capacitance change is measured as a function of sample bias. A ...Oxide capacitance; Dopant profile; Oxide layer; Scanning capacitance microscopy1996-01
149 Gondolo, PaoloDirect detection of neutralino dark matter in nonstandard cosmologiesWe compute the neutralino direct detection rate in nonstandard cosmological scenarios where neutralinos account for the dark matter of the Universe. Significant differences are found when such rates are compared with those predicted by the standard cosmological model. For b-ino-like neutralinos, the...Neutralinos2008-02
150 Williams, Clayton C.Direct imaging of SiO2 thickness variation on Si using modified atomic force microscopeFabrication techniques of metal-oxide-semiconductor ~(MOS) transistors have been improved very rapidly during the last several decades. With this trend, scaling down of MOS transistors is necessary to improve the speed of circuits and the packing density of discrete devices. Both lateral and vertic...Silicon dioxide; Oxide layer; Phosphorus ions; Oxide capacitance; Dopant profile1996-03-01
151 Vardeny, Zeev ValentineDirectional emission from asymmetric microlaser resonators of ∏-conjugated polymersA ∏-conjugated polymer film was fabricated into an asymmetric microlaser resonator having a quadrapole deformation with irregular boundaries and a Q factor of 600. At high excitation intensities above the threshold for lasing, we observed multimode laser emission spectra and directional emission a...Directional emission; Asymmetric microlaser resonators; pi-conjugated polymers; DOO-PPV; poly(dioctyloxy) phenylene vinylene2004
152 Gondolo, PaoloDirectional recoil rates for WIMP direct detectionNew techniques for the laboratory direct detection of dark matter weakly interacting massive particles (WIMPs) are sensitive to the recoil direction of the struck nuclei.We compute and compare the directional recoil rates dR/d cosθ, (where θ is the angle measured from a reference direction in th...WIMP; Weakly interacting massive particles; WMAP 3; Directional recoil; Halo models2008-02
153 Symko, Orest GeorgeDiscrete spatial filtering with SQUID gradiometers in biomagnetismFirst-, second-, and third-order gradiometers used in detecting biomagnetic signals are analyzed as spatial niters. Their transfer functions independent of the source to be measured are presented and both the magnitude and phase characteristics of the transfer functions are analyzed. The distortion ...Spatial filtering; SQUID gradiometers; Fourier transform1986
154 Vardeny, Zeev ValentineDisorder-induced TA Raman lines in mixed Cu-halide crystalsThe Raman spectra of CuClxBr1=x and CuBrxI1=x solid solutions are shown to contain extremely intense disorder-induced first-order TA phonons. The intensity of these lines is a function of the concentration x, and is highest in CuCl0.6oBr0.40. The TA spectrum, well resolved at low temperature, fits...Cuprous halides; CuBr; CuCl; CuI; mixed Cu-halide crystals1979-03
155 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Dispersion of resonant Raman scattering in ∏-conjugated polymers: role of the even parity excitonsResonant Raman scattering dispersion of the most strongly coupled phonon frequencies with the excitation laser photon energy is measured in terms of a dispersion rate parameter D and quantified in a variety of p conjugated polymer films. D was found to be large in nonluminescent polymers and small i...Resonant raman scattering; Even parity excitons1997-09
156 Symko, Orest GeorgeDoes the quasicrystal AlCuFe follow Ohm's law?We present the first measurements of the electrical I-V characteristics of AlCuFe quasicrystalline thin films processed by solid state interdiffusion of magnetron sputtered Al, Cu, and Fe layers. Despite the peculiar electronic properties of quasicrystals, our results show that those samples follow ...AlCuFe; Quasicrystal1994-10
157 Vardeny, Zeev ValentineDouble-modulation electro-optic sampling for pump-and-probe ultrafast correlation measurementsWe describe a novel electro-optic double-modulation (DM) sampling technique for ultrafast transient spectroscopy, which is characterized by a superior signal-to-noise ratio compared to that of a regular single-modulation technique. DM is achieved by a combined effect of a radio-frequency modulation,...Double-modulation; Electro-optic sampling; Ultrafast transient spectroscopy; Pump; Probe1998
158 Gondolo, PaoloDUSEL theory white paperThe scientific case for a Deep Underground Science and Engineering Laboratory [DUSEL] located at the Homestake mine in Lead, South Dakota is exceptional. The site of this future laboratory already claims a discovery for the detection of solar neutrinos, leading to a Nobel Prize for Ray Davis. Moreov...DUSEL; Deep Underground Science and Engineering Laboratory; Proton decay2008
159 Mattis, Daniel C.Dynamic properties of a nonsuperfluid Bose liquid in the random-phase approximationThe dynamic structure factor S(k,w) of a nonideal Bose liquid is calculated within the random-phase approximation and compared with neutron scattering data by Cowley and Woods for liquid helium in the temperature range Tλ<T≤4.2°K, with the conclusion that the model is wholly inadequate. A low-f...Bose liquid; Random-phase approximation; Overdamping1974-11
160 Wu, Yong-ShiDynamics of giant-gravitons in the LLM geometry and the fractional quantum Hall effectThe LLM's 1/2 BPS solutions of IIB supergravity are known to be closely related to the integer quantum Hall droplets with filling factor v = 1, and the giant gravitons in the LLM geometry behave like the quasi-holes in those droplets. In this paper we consider how the fractional quantum Hall effect ...2006
161 Mattis, Daniel C.Dynamics of quasiparticles in the two-dimensional Hubbard modelThe Hubbard model at half-filling is a collective, antiferromagnetic insulator. We study added electrons or holes. The insulating energy gap and the dispersion of the added carriers are calculated variationally in two dimensions with use of a Monte Carlo evaluation of the electronic correlation f...Dispersion; Electrons; Carriers1990
162 Ailion, David CharlesDynamics of the pinned modulation wave in incommensurate bis (4-chlorophenyl) sulfone (BCPS)We show that both the anomalously huge resonance-frequency dependence of the 3 5Cl nuclear quadrupole resonance (NQR) spin-lattice relaxation time in BCPS, reported here for the first time, and its anomalous temperature dependence can be explained by large-scale fluctuations of the pinned modulation...NQR; Spin-lattice; Relaxation-time; Pinned modulation wave2002
163 Gondolo, PaoloEffect of a late decaying scalar on the neutralino relic densityIf the energy density of the Universe before nucleosynthesis is dominated by a scalar field Ø that decays and reheats the plasma to a temperature TRH smaller than the standard neutralino freeze-out temperature, the neutralino relic density differs from its standard value. In this case, the relic de...Neutralinos; Relic density; Reheating temperature2006-10
164 Mattis, Daniel C.Effect of band structure on ferromagnetism*We extend Nagaoka's study of the ferromagnetism of nearly half-filled bands in the infinite-repulsion limit of the Hubbard model by including next-nearest-neighbor tight-binding overlap matrix elements K2. Particles can now get past one another, even in one dimension. We find corroboration of Nagaok...Eigenstates; Spin waves1974-08
165 Vardeny, Zeev ValentineEffect of bias illumination on photoinduced absorption decay in ?-Si:HZeldov and Weiser1 proposed a model to explain the influence of optical biasing on the decay of photoinduced absorption (PA) in ?-Si:H at high temperatures observed by Pfost, Vardeny, and Tauc.2 This model differs from the model originally used2 for interpreting the experimental data at temperatures...Optical biasing; Bias illumination; Photoinduced absorption decay; a-Si:H; Amorphous silicon1985
166 Sokolsky, PierreEffect of clouds on apertures of space-based air fluorescence detectorsSpace-based ultra-high-energy cosmic ray detectors observe fluorescence light from extensive air showers produced by these particles in the troposphere. Clouds can scatter and absorb this light and produce systematic errors in energy determination and spectrum normalization. We study the possibilit...Fluorescence; Cloud detection; Extensive air showers2004-01
167 Symko, Orest GeorgeEffect of crystal field on the magnetization of dilute hcp alloysMagnetization measurements on very dilute single-crystal alloys of Mg-Mn, Zn-Mn, and Zn-Cr in the temperature range of 2-0.008 K show that the ground state of these systems is determined by fine-structure splitting. For Mg-Mn the fine-structure constant D is +0.006 K with an effective spin of f whil...HCP alloys; Crystal field; Magnetization; Mg-Mn; Zn-Mn; Zn-Cr1982-04
168 Gondolo, PaoloEffect of dark matter on the first stars: a new phase of stellar evolutionDark matter (DM) in protostellar halos can dramatically alter the current theoretical framework for the formation of the first stars. Heat from supersymmetric DM annihilation can overwhelm any cooling mechanism, consequently impeding the star formation process and possibly leading to a new stellar ...Dark stars2008
169 Mishchenko, EugeneEffect of electron-electron interactions on the conductivity of clean grapheneMinimal conductivity of a single undoped graphene layer is known to be of the order of the conductance quantum, independent of the electron velocity. We show that this universality does not survive electron-electron interaction, which results in nontrivial frequency dependence. We begin with analyzi...Optical conductivity; Perturbation theory2007-05
170 Boehme, ChristophEffect of exchange coupling on coherently controlled spin-dependent transition ratesThe effect of exchange interactions within spin pairs on spin-dependent transport and recombination rates through localized states in semiconductors during coherent electron-spin resonant excitation is studied theoretically. It is shown that for identical spin systems, significant quantitative diff...Spin coherence; Electron spin nutations2008-06
171 Mattis, Daniel C.Effect of exciton hopping upon the mass of an excitonA plausible formula derived in a previous paper for the mass Mn* of an exciton in an nth bound state of the electron-hole binding potential is extended so as to include the effect of an exciton-hopping (or Heller-Marcus) mechanism upon Mn*.Frenkel excitons; Exciton-hopping; Heller-Marcus energy; Binding potential1985-10
172 Gerton, JordanEffect of magnetic Gd impurities on the superconducting state of amorphous Mo-Ge thin films with different thickness and morphologyWe studied the effect of magnetic doping with Gd atoms on the superconducting properties of amorphous Mo70Ge30 films. We observed that in uniform films deposited on amorphous Ge, the pair-breaking strength per impurity strongly decreases with film thickness initially and saturates at a finite value ...2012-01-01
173 Rogachev, AndreyEffect of morphology on the superconductor-insulator transition in one-dimensional nanowiresWe study the effect of morphology on the low-temperature behavior of superconducting nanowires which vary in length from 86 nm to 188 nm. A well-defined superconductor-insulator transition is observed only in the family of homogeneous wires, in which case the transition occurs when the normal resist...One-dimensional wires; Superconductor-insulator transition; Homogeneous wires; Inhomogeneous wires; Morphology; Low-temperature behavior2004-05
174 Gondolo, PaoloThe effect of quark interactions on dark matter kinetic decoupling and the mass of the smallest dark halosThe kinetic decoupling of dark matter (DM) from the primordial plasma sets the size of the first and smallest DM halos. Studies of the DM kinetic decoupling have hitherto mostly neglected interactions between the DM and the quarks in the plasma. Here we illustrate their importance using two framewor...2012-01-01
175 Symko, Orest GeorgeEffect of RKKY interactions on the magnetization of dilute magnetic alloys with hcp hostsThe magnetization due to the presence of magnetic impurities dissolved dilutely in nonmagnetic H.C.P. host metals has been calculated assuming a fine structure splitting by an axially symmetric crystal field and an RKKY interaction between the impurities. To compute the RKKY contribution, the inte...RKKY interactions; Dilute magnetic alloys; HCP hosts; MgMn; ZnMn1981
176 Mattis, Daniel C.Effect of spin variables and exciton motion on ground-state properties of the "trionWe solve a quantum three-body problem involving two holes and a single electron ("trion") in a two-band Hubbard model. The particles' spin and the exciton hopping matrix element are all included. We compare the results with those of a previous paper, in which these additional complications were abs...Three-body problem; Trion; Bond energies1983-03
177 Williams, Clayton C.; Stringfellow, Gerald B.Effect of substrate misorientation on ordering in Ga0.5In0.5POrdering produced in Gao.5Ino.5P epitaxial layers grown by OMVPE can be controlled by variations in the substrate misorientation as well as the growth temperature and the growth rate. The ordering produced at a growth temperature of 620°C and a relatively low growth rate of 0.5 /μm/hr is found to ...Ga0.5In0.5P; Epitaxial layers; Epitaxial growth; OMVPE1994
178 Ailion, David CharlesEffect of the translational diffusion mechanism on the low-field NMR spin-lattice relaxation time in the rotating reference frame: calculation of order parameterThe effect of the translational-diffusion mechanism on the low-field NMR spin-lattice relaxation time in the rotating reference frame is calculated for simple cubic, body-centered cubic, and face-centered cubic lattices. The results of these calculations suggest a new method for determining the pref...NMR; Nuclear magnetic resonance; Lattices; Relaxation time1968
179 Vardeny, Zeev ValentineThe effects of charge injection in single-wall carbon nanotubes studied by charge-induced absorptionWe studied direct charge injection in a heterogeneous film of single-wall carbon nanotubes using the technique of charge-induced absorption. We found that the injected charges screen the excitons in the semiconducting tubes, reducing their binding energy and transferring oscillator strength from the...2011
180 Dawson, KyleThe effects of charge transfer inefficiency (CTI) on galaxy shape measurementsWe examine the effects of charge transfer inefficiency (CTI) during CCD readout on the demanding galaxy shape measurements required by studies of weak gravitational lensing. We simulate a CCD readout with CTI such as that caused by charged particle radiation damage in space-based detectors. We verif...2010
181 Mattis, Daniel C.Effects of orbital degeneracy on a magnetic impurity in a nonmagnetic metalWe study the Green's-function equations for a version of the two-orbital Anderson model of a magnetic impurity, in an approximation scheme that displays the logarithmic anomalies and enables the Kondo temperature Tĸ to be calculated as a function of the parameters. The nature of the solutions is ex...Orbital degeneracy; Magnetic impurities; Nonmagnetic metal; Kondo temperature; Anomalous resonances1969-02
182 Gondolo, PaoloEffects of the Sagittarius dwarf tidal stream on dark matter detectorsThe Sagittarius dwarf tidal stream may be showering dark matter onto the solar neighborhood, which can change the results and interpretation of direct detection searches for weakly interacting massive particles (WIMPs). Stars in the stream may already have been detected in the solar neighborhood, an...Sagittarius dwarf galaxy; Sgr stream; WIMP; Weakly interacting massive particles2004-03
183 Vardeny, Zeev ValentineEfficiency enhancement of an organic light-emitting diode with a cathode forming two-dimensional periodic hole arrayWe fabricated an organic light-emitting diode using a ∏-conjugated polymer emissive layer sandwiched between two semitransparent electrodes: an optically thin gold film anode, whereas the cathode was in the form of an optically thick aluminum (Al) film with patterned periodic subwavelength two-dim...pi-conjugated polymers; Organic light-emitting diode; OLED2005
184 Lupton, John MarkEfficient dipole-dipole coupling of Mott-Wannier and Frenkel excitons in (Ga,In)N quantum well/polyfluorene semiconductor heterostructuresWe investigate interactions between Mott-Wannier (MW) and Frenkel excitons in a family of hybrid structures consisting of thin organic (polyfluorene) films placed in close proximity (systematically adjusted by GaN cap layer thickness) to single inorganic [(Ga, In)N/GaN] quantum wells (QWs). Charac...Mott-Wannier; Frenkel; Excitons; Dipole-dipole coupling; Semiconductor heterostructures2007-07
185 Mattis, Daniel C.Eigenfunction localization in dilute lattices of various dimensionalitiesAs a fraction of bonds p is removed from a lattice, we find a threshold PQ above which all eigenstates are nonpropagating (Anderson localized). This occurs well before the classical percolation threshold. For example, in two dimensions where the classical threshold is pc = 1/2 , we find PQ = 0.Eigenstates; Dilute lattices1981-05
186 Bromley, Benjamin C.Eigenspectral computtations for linear gravity and nonlinear toy modelsThe periodic standing-wave approach to binary inspiral assumes rigid rotation of gravitational fields and hence helically symmetric solutions. To exploit the symmetry, numerical computations must solve for "helical scalars," fields that are functions only of corotating coordinates, the labels on the...Binary black holes; General relativity; Standing wave2006
187 Mattis, Daniel C.Eigenstates of excitons near a surfaceThe exact eigenstates and energies of an electron and a hole of equal effective masses, with an attractive δ-function interaction and hard-wall repulsion at the surfaces of a solid, are classified and obtained explicitly for a solid of arbitrary thickness. Both bound and scattering states of the e...Eigenstates; Frenkel excitons1978-10
188 Mattis, Daniel C.Eigenstates of N excitons and one holeWe solve for the eigenstates and energy eigenvalues of N immobile Frenkel excitons (a relatively trivial proposition) and of N such excitons plus one hole (which for large N can only be done in one dimension). We also guess that a charged globule, consisting of N excitons and O(N) holes, can be stab...Eigenstates; Frenkel excitons; Many-body problem1983-04
189 Vardeny, Zeev ValentineElectrical and optical studies of gap states in self-assembled molecular aggregatesWe fabricated a variety of two-terminal devices using self-assembled monolayers (SAM) of solid-state mixtures comprised of molecular "wires" [1,4-methane-benzenedithiol (Me-BDT)] and molecular insulator "spacers" [1-pentanethiol], which were prepared at various molar concentrations ratio, r of wires...Gap states; Self-assembled molecular aggregates2007
190 Boehme, ChristophElectrical detection of coherent 31P spin quantum statesIn recent years, a variety of solid-state qubits has been realized, including quantum dots [1, 2], superconducting tunnel junctions [3, 4] and point defects [5, 6]. Due to its potential compatibility with existing microelectronics, the proposal by Kane [7, 8] based on phosphorus donors in Si has als...Spin quantum states; Qubits; Rabi flops2006-11-19
191 Boehme, ChristophElectrical detection of spin coherence in siliconExperimental evidence is presented showing that photocurrents in silicon can be used as highly sensitive readout probes for coherent spin states of localized electrons, the prime candidates for quantum bits in various semiconductor based quantum computer concepts. Conduction electrons are subjected ...Spin coherence; Electronic transitions; Rabi oscillation2003-12
192 Vardeny, Zeev ValentineElectroabsorption spectroscopy of luminescent and nonluminescent ∏-conjugated polymersWe have measured the quadratic electroabsorption (EA) spectrum of a variety of soluble luminescent and nonluminescent p-conjugated polymer films in the spectral range of 1.5-4.5 eV. The luminescent polymers include MEH and DOO derivatives of poly(phenylene-vinylene), poly(phenylene ethylene), and ...Electroabsorption spectroscopy; pi-conjugated polymers1997-12
193 Vardeny, Zeev ValentineElectroabsorption spectroscopy of single walled nanotubesWe have measured the electric field modulated absorption of a sample of single-walled nanotubes (SWNT) suspended in a solid polyvinyl alcohol matrix. The electroabsorption (EA) spectrum roughly follows the first derivative of the absorption with respect to photon energy, scales quadratically with t...Electroabsorption spectroscopy; Single-walled nanotubes; SWNT2005
194 Vardeny, Zeev ValentineElectromodulated photoinduced absorption; a new spectroscopy in ∏-conjugated polymer/C60-blendsWe have applied the electromodulated photoinduced absorption (EPA) technique to a variety of C 6 0 -doped and pristine luminescent conducting polymer films. EPA measures the electric field-related change of the absorption in the sample as a result of above-gap illumination. An electric field leads t...Electromodulated photoinduced absorption; EPA; C60 doping; Electromodulated photoluminescence; EPL; Polaron pair polarizability1997
195 Vardeny, Zeev ValentineElectromodulation of charge-transfer photoexcitations in pristine and C60-doped conjugated polymersWe study the effect of an electric field of up to 100 kV/cm on photoexcitations in pristine and C60-doped p-conjugated polymers by electromodulated photoinduced absorption (EPA). In EPA, we measure changes in the photoinduced absorption of a polymer film induced by an electric field. The dominant ...Electromodulation; Charge-transfer photoexcitations; Photoinduced absorption; pi-conjugated polymers; Electromodulation spectroscopy1999-04
196 Mattis, Daniel C.Electron states in random alloys with short-range orderWe present an accurate and economical iterative method of calculating the energy levels of a disordered or partly ordered random alloy. Results presented for one- and three-dimensional simple cubic lattices compare favorably with exact calculations. We also present the systematic effects of partia...Random alloys; Density of state1977-04
197 Williams, Clayton C.Electron tunneling detected by electrostatic forceA method is introduced for measuring the tunneling of electrons between a specially fabricated scanning probe microscope tip and a surface. The technique is based upon electrostatic force detection of charge as it is transferred to and from a small (10217 F) electrically isolated metallic dot on the...Electrons; Tunneling events; Electrostatic force microscopy2000
198 Mishchenko, EugeneElectron-lattice kinetics of metals heated by ultrashort laser pulsesWe propose a kinetic model of transient nonequilibrium phenomena in metals exposed to ultrashort laser pulses when heated electrons affect the lattice through direct electron-phonon interaction. This model describes the destruction of a metal under intense laser pumping. We derive the system of equa...Electron-lattice kinetics; Thermoconductivity; electron temperature; Lattice deformation1999-01
199 Mattis, Daniel C.Electron-phonon interaction in two dimensions: the case for strong coupling in high-Tc superconductorsA particular model interaction between electrons and acoustic phonons is found to cause electrons to become weakly "self-trapped" for an arbitrary filling factor in d=2, but not in d=1 nor, for different reasons, in d>3. To the extent that electron kinetic energy is reduced in d=2, the electronic in...Strong coupling1987-09
200 Mishchenko, EugeneElectronic Raman scattering in a magnetic fieldRaman scattering in a magnetic field is proposed as a possible method to solve the problem of whether the light scattering in high-Tc superconductors comes from conduction electrons or not. The electronic Raman light scattering in a magnetic field is studied theoretically. The semiclassical approa...Raman scattering1996-01
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