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CreatorTitleDescriptionSubjectDate
1 Heavy-light decay constants: conclusions from the Wilson actionWe report on the results of a MILC collaboration calculation of fB, fBs , fD, fDs and their ratios. We discuss the most important errors in more detail than we have elsewhere.Decay constants; Wilson action; Staggered quarks1999-03
2 Masses of high-redshift clusters via SZ effect observationsWe present Sunyaev-Zel'dovich Effect (SZE) observations of distant, highly X-ray luminous clusters of galaxies. We use the SZE data to constrain their total masses, independent of X-ray observations. To do this, we assume the clusters have the same gas mass fraction as that derived from SZE measure...Sunyaev-Zel'dovich Effect; X-rays; Redshift2002
3 Kinetic theory of shot noise in nondegenerate diffusive conductorsWe investigate current fluctuations in nondegenerate semiconductors, on length scales intermediate between the elastic and inelastic mean free paths. We present an exact solution of the nonlinear kinetic equations in the regime of space-charge limited conduction, without resorting to the drift app...Shot noise; Conductors; Boltzmann equation1999-08
4 New two-point calibration method for platinum resistance thermometers for the range 75-400KIn this paper we describe a new method for calibrating high quality platinum resistance thermometers to ±0.01 "C over the temperature range 75-400 K. This method requires resistance measurements at only two temperatures (liquid nitrogen and the ice point) in contrast to other methods which require ...Platinum; Resistance thermometers; Physics instruments1969
5 Extinction of antiferromagnetism by holes in CuO2The introduction of a sufficient number of holes into antiferromagnetic planes of Cu02 in La-Cu-O and Y-Ba-Cu-O causes antiferromagnetism to disappear at a critical density xc, beyond which superconductivity occurs. We investigate two competing tendencies, which determine the dependence of xc on the...Antiferromagnets1991-08
6 Observation of molecular vibrations in real timeIn a recent Letter Rosker, Wise, and Tang1 have reported ultrafast optical measurements on two large dye molecules, malachite green and nile blue 690. Using the transmission-correlation technique with 40-fs light pulses, they measured photoinduced changes in optical transmission and found a resp...Molecular vibrations; Nile blue 690; Dyes1986
7 Tunneling and the spectrum of the Potts modelThe three-dimensional, three-state Potts model is studied as a paradigm for high-temperature quantum chromodynamics. In a high-statistics numerical simulation using a Swendson-Wang algorithm, we study cubic lattices of dimension as larger as 643 and measure correlation functions on long lattices of ...Potts model; Tunneling; Transfer matrix; Phase transitions1993-05
8 Illumination-induced metastable polaron-supporting state in poly(p-phenylene vinylene) filmsWe found an illumination-induced metastable polaron-supporting state in films of a soluble derivative of poly-p-phenylene vinylene (MEH-PPV). Pristine, nonilluminated MEH-PPV polymer films do not show longlived photogenerated polarons. Prolonged UV illumination, however, is found to induce a revers...Metastable polaron-supporting state; Poly(p-phenylene vinylene); PPV; MEH-PPV; Excitons2007-07
9 Resonant Raman scattering from amplitude modes in trans-(CH)x and -(CD)xThe three resonantly enhanced Raman vibrations in trans-(CK)x and ~(CD)X are described in terms of amplitude modes associated with the Peierls gap. The dispersion in the Raman-line profiles is explained by inhomogeneity. A narrow distribution of the effective electron-phonon coupling constant is re...Peierls gap1983-12
10 Annual 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
11 Ground-state energy of Heisenberg antiferromagnet for spins s=1/2 and s=1 in d=1 and 2 dimensionsA simple real-space renormalization method yields the ground-state energy of the Heisenberg antiferromagnet. We find the ground-state energy per spin for s=1/2 (-0.4438 in ID , -0.6723 in 2D ) and s = 1 (-1.388 in ID and -1.907 in 2D) to three-figure accuracy, using properties of relatively small o...Ground-state energy; Heisenberg antiferromagnet; Long-range order1988-07
12 Optical and transport studies of single molecule tunnel junctions based on self-assembled monolayersWe have fabricated a variety of novel molecular tunnel junctions based on self-assembled-monolayers (SAM) of two-component solid-state mixtures of molecular wires (1,4 methane benzene-dithiol; Me-BDT with two thiol anchoring groups), and molecular insulator spacers (1-pentanethiol; PT with one thio...2005-09
13 QCD thermodynamics with two flavors at Nt=6The first results of numerical simulations of quantum chromodynamics on the Intel iPSC/860 parallel processor are presented. We performed calculations with two flavors of Kogut-Susskind quarks at Nt = 6 with masses of 0.15T and 0.075T (0.025 and 0.0125 in lattice units) in order to locate the crosso...Kogut-Susskind quarks; Crossover temperature; Chiral symmetry; Polyakov loop; Phase transitions1992-05
14 Hidden massive Dirac fermions in effective field theory for integral quantum Hall transitionsIntegral quantum Hall plateau transitions in a planar lattice system due to gap collapse can be described by an effective field theory with Dirac fermions. We discuss how to reproduce the correct integral values for the Hall conductance sxy before and after the plateau transition, which are dictat...Dirac fermions; Vorticities; Edge states; Hall conductance1996-08
15 Spatial mapping of ordered and disordered domains of GaInP by near-field scanning optical microscopy and scanning capacitance microscopyImaging of topography, locally induced photoluminescence and Fermi-level pinning in adjacent ordered and disordered domains on a cleaved GaInP sample is performed using a near-field scanning optical microscope and scanning capacitance microscope at room temperature in air. Highly localized photolumi...Gallium Phosphides; Surface Structure; Photoluminescence1996-04-13
16 Renormalization group equations and the Lifshitz point in noncommutative Landau-Ginsburg theoryA one-loop renormalization group (RG) analysis is performed for noncommutative Landau-Ginsburg theory in an arbitrary dimension. We adopt a modern version of the Wilsonian RG approach, in which a shell integration in momentum space bypasses the potential IR singularities due to UV-IR mixing. The mo...2002-02
17 Zero temperature string breaking in lattice quantum chromodynamicsThe separation of a heavy quark and antiquark pair leads to the formation of a tube of flux, or ‘‘string,'' which should break in the presence of light quark-antiquark pairs. This expected zero-temperature phenomenon has proven elusive in simulations of lattice QCD. We study mixing between the ...String breaking; Wilson loop2001-09
18 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
19 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
20 Picosecond photomodulation study of nanocrystalline hydrogenated siliconWe have extended our photomodulation studies of nc-Si:H to the picosecond time domain. We measured the decays of photoinduced reflectivity with lOOfs temporal resolution as a function of. light intensity. Comparison with the data obtained on a-Si:H and c-Si indicates that ultrafast trapping and reco...Picosecond photomodulation; Nanocrystalline silicon1990
21 High sensitivity nuclear quadrupole resonance approach for detection of modulation wave motion in incommensurate systemsIn contrast to conventional NMR techniques that use magnetic field gradients (MFCs) to detect the diffusion of moving atoms, we have developed a highly sensitive approach for detecting electric field gradient (EFG) fluctuations seen by stationary atoms. These EFG fluctuations were observed in the ...NMR; MFG; Magnetic field gradients; Diffusion constants; Atoms; Nuclei1995
22 Photoinduced quantum interference antiresonances in ∏-conjugated polymersWe observed photoinduced quantum interference antiresonances between several discrete infraredactive vibrations and the lower-polaron continuous absorption band in a series of p-conjugated polymer films having superior planar orders, where the polaron transition energy is relatively small. The phot...pi-conjugated polymers; Antiresonances; Fano-type antiresonances2002-05
23 Optically detected magnetic resonance studies of undoped a-Si:HPhotogenerated carrier dynamics in undoped a-Si:H have been studied by photoinduced absorption (PA), photoluminescence (PL) and their respective optically detected magnetic resonances: PADMR and PLDMR. We have detected for the first time the "g = 4" resonance in PADMR in addition to the previously ...Undoped a-Si:H; Amorphous silicon; Carrier dynamics1996
24 Equation of state for two flavor QCD at Nt=6We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)21 and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)21. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms ...Phase transitions; Quark-gluon plasma; Chiral symmetry1997-06
25 Dark 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
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