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CreatorTitleDescriptionSubjectDate
326 Mishchenko, Eugene; Raikh, Mikhail E.Tunneling between two-dimensional electron layers with correlated disorder: anomalous sensitivity to spin-orbit couplingTunneling between two-dimensional electron layers with mutually correlated disorder potentials is studied theoretically. Due to this correlation, the diffusive eigenstates in different layers are almost orthogonal to each other. As a result, a peak in the tunnel I-V characteristics shifts towards s...Spin-orbit coupling2006-11
327 Kieda, David B.Status of the VERITAS observatoryAbstract. VERITAS, an Imaging Atmospheric Cherenkov Telescope (IACT) system for gammma-ray astronomy in the GeV-TeV range, has recently completed its first season of observations with a full array of four telescopes. A number of astrophysical gamma-ray sources have been detected, both galactic and e...2008
328 Vardeny, Zeev ValentineExcited-state relaxation in ∏-conjugated polymersWe study ultrafast relaxation processes of odd- (Bu) and even-parity (Ag) exciton states in poly(p-phenylene vinylene) derivatives. The Bu states are studied using a regular two-beam pump-and-probe spectroscopy, which can monitor vibronic relaxation and exciton diffusion. In order to observe the A...Ultrafast relaxation; Excited-state relaxation; pi-conjugated polymers; PPV2002-05
329 Wu, Yong-ShiQuantum phase transition and engineering in two-component BEC in optical latticesIn this paper we review recent progress in studying quantum phase transitions in one- and two-component Bose-Einstein condensates (BEC) in optical lattices. These phase transitions involve the emergence and disappearance of quantum coherence over whole optical lattice and of linear superposition of...2003
330 Vardeny, Zeev ValentinePhotoexcitation dynamics and laser action in solutions and films of PPE-PPV copolymerWe used a variety of ultrafast and steady-state spectroscopy techniques to study the photoexcitation dynamics and laser action in dilute and concentrated solutions and in thin films of poly(phenylene-ethynylene)/ poly(phenylene-vinylene) [PPE-PPV] copolymer. We found that the primary photoexcitatio...Photoexcitation dynamics; Laser action; PPE-PPV copolymers2004-04
331 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
332 Vardeny, Zeev ValentineRecent advances in organic spin-valve devicesOrganic Spintronics has been considered to be the physics and applications of spin polarized electron injection, transport, manipulation and detection in organic diodes by the application of an external magnetic field. The prototype device is the organic spin-valve (OSV), which is based on an organi...Spin-valve devices; Organic Spintronics; Spin polarized carrier injection; OSV2010-02
333 Bromley, Benjamin C.Variations on debris disks: icy planet formation at 30-150 AU for 1-3 M. main-sequence starsWe describe calculations for the formation of icy planets and debris disks at 30-150 AU around 1-3 M. stars. Debris disk formation coincides with the formation of planetary systems. As protoplanets grow, they stir leftover planetesimals to large velocities. A cascade of collisions then grinds the l...Icy planets; Planet formation; Debris disks; Main-sequence stars2008
334 Vardeny, Zeev ValentineStudies of resonant and preresonant femtosecond degenerate four-wave mixing in unoriented conducting polymersDegenerate four-wave mixing with femtosecond time resolution is used to measure the magnitude and transient response of the third-order nonlinear optical susceptibility x(3) (ω;ω, -ω,ω) at 620 nm in nonoriented conducting polymers including polydiacetylene, polyacetylene, polyaniline, polydieth...Pi-conjugated polymers1991
335 Mishchenko, EugenePlasmon attenuation and optical conductivity of a two-dimensional electron gasIn a ballistic two-dimensional electron gas, the Landau damping does not lead to plasmon attenuation in a broad interval of wave vectors q≤kF . Similarly, it does not contribute to the optical conductivity σ(ω,q) in a wide domain of its arguments, EF>ω>qvF , where EF , kF , and vF are, respec...Optical conductivity; Plasmon-phonon conversion; Landau damping2004-05
336 Wu, Yong-ShiThermal activation of quasiparticles and thermodynamics of fractional quantum Hall liquidsQuasielectrons and quasiholes in the fractional quantum Hall liquids obey fractional (including nontrivial mutual) exclusion statistics. Their statistics matrix can be determined from several possible state-counting schemes, involving different assumptions on statistical correlations. Thermal activ...Quasielectrons; Quasiholes; Exclusion statistics1998-04
337 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
338 Ailion, David CharlesThermal fluctuations and NMR spectra of incommensurate insulatorsThe effects of thermal order-parameter fluctuations on the NMR line shape of incommensurate systems are evaluated within the mean-field Landau theory and the results are compared with the 8 7Rb and 3 9K 1/2 -1/2 NMR spectra of Rb2ZnCl4 and K2Se04 just below the paraelectric-incommensurate transition...NMR spectra; Thermal fluctuations; Line shapes; Incommensurate insulators1994
339 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
340 DeTar, CarletonThermodynamics with 3 and 2+1 flavors improved staggered quarksWe present preliminary results [1] from exploring the phase diagram of finite temperature QCD with three degenerate flavors and with two light flavors and the mass of the third held approximately at the strange quark mass. We use an order _x000B_2 sa2, a4 Symanzik improved gauge action and an orde...Staggered quarks2002-03
341 Wu, Yong-ShiNumerical study of the three-dimensional random-field Ising model at zero and positive temperatureIn this paper the three-dimensional random-field Ising model is studied at both zero temperature and positive temperature. Critical exponents are extracted at zero temperature by finite size scaling analysis of large discontinuities in the bond energy. The heat capacity exponent α is found to be n...Bond energies; Ground states2006-08
342 Vardeny, Zeev Valentine; Gellermann, WernerRaman scattering gain in DOO-PPV filmsWe have investigated the optical emission characteristics of poly(2,5-dioctyloxy-p-phenylenevinylene) (DOO-PPV) thin films under high intensity ps pulsed laser excitation (Ipump > 1 MW/ cm2). We observed that the emission spectrum consist of a spectrally narrowed emission (SNE) band (FWHM ~ 10 nm)...DOO-PPV; Raman scattering gain; Stimulated emission; Strongly coupled vibrations1997
343 Ailion, David CharlesThermal fluctuations and NMR spectra of incommensurate systemsIn the presence of thermal fluctuations the incommensurate NMR line shape is a convolution of a static inhomogeneous with a dynamic homogeneous line shape which can be determined separately by 2D NMR. The form of the dynamic line shape and its variation over the inhomogeneous NMR spectrum permit a ...Thermal fluctuations; NMR; Incommensurate systems; Line shape1992
344 Mattis, Daniel C.Soluble extension of the Ising modelIn this note we wish to relate a somewhat trivial, but surprising, soluble extension of the multidimensional Ising model. Our extension was motivated by recent experiments on a real material, dysprosium aluminum garnet (DyAlG), which closely resembles an ideal three-dimensional Ising model,1 except ...Dysprosium aluminum garnet; Ising spin1966-05
345 Mattis, Daniel C.Exactly soluble model of interacting electronsWe diagonalize a many-fermion Hamiltonian consisting of terms quadratic as well as quartic in the field operators. A dual spectrum of eigenstates is an interesting result. We also derive a formula for obtaining the free energy at finite temperature.Eigenstates; Free energy; Excitation spectrum1972
346 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
347 DeTar, CarletonImproving flavor symmetry in the Kogut-Susskind hadron spectrumWe study the effect of modifying the coupling of Kogut-Susskind quarks to the gauge field by replacing the link matrix in the quark action by a ‘‘fat link,'' or sum of link plus three-link paths. Flavor symmetry breaking, determined by the mass difference between the Goldstone and non-Goldston...Kogut-Susskind quarks; Flavor symmetry; Fat links1997-02
348 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
349 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
350 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
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