|
|
Creator | Title | Description | Subject | Date |
226 |
|
Gerton, Jordan | Photoassociative frequency shift in a quantum degenerate gas | A light-induced frequency shift is observed in single-photon photoassociative spectra of magnetically trapped, quantum degenerate 7Li. The shift is a manifestation of the coupling between the threshold continuum scattering states and discrete bound levels in the excited-state molecular potential in... | | 2001-10 |
227 |
|
DeTar, Carleton | Light hadrons with improved staggered quarks: approaching the continuum limit | We have extended our program of QCD simulations with an improved Kogut-Susskind quark action to a smaller lattice spacing, approximately 0.09 fm. Also, the simulations with a ≈ 0.12 fm have been extended to smaller quark masses. In this paper we describe the new simulations and computations of the... | Staggered quarks; Hadronic decay | 2004-11 |
228 |
|
Vardeny, Zeev Valentine | Cylindrical micolasers and light emitting devices from conducting polymers | Substantially 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; Microlasers | 1998 |
229 |
|
Lupton, John Mark | Molecular thermometer based on long-lived emission from platinum octaethyl porphyrin | A highly sensitive molecular thermometer based on platinum octaethyl porphyrin, which can be employed in a range of environments, is presented. The thermal activation of the emission spectrum results in a change in emission intensity by an order of magnitude over a temperature range of 45 K about ro... | Molecular thermometer; Platinum octaethyl porphyrin | 2002 |
230 |
|
Wu, Yong-Shi | Mutual exclusion statistics between quasiparticles in the fractional quantum Hall effect | In this paper we propose a new assignment for mutual exclusion statistics between quasielectrons and quasiholes in the fractional quantum Hall effect. In addition to providing numerical evidence for this assignment, we show that the physical origin of this mutual statistics is a novel hard-core co... | Exclusion statistics | 1996-10 |
231 |
|
Williams, Clayton C. | Modeling and experimental investigation of cantilever dynamics in force detected single electron tunneling | The dynamic response of a voltage biased oscillating cantilever probe is investigated through experimental and theoretical analysis as it approaches a dielectric surface. When the tip reaches the appropriate gap single electron tunneling events are detected between the metallic tip and the surface. ... | Oscillating cantilever probe; Electron tunneling | 2004 |
232 |
|
Mattis, Daniel C. | Effects of orbital degeneracy on a magnetic impurity in a nonmagnetic metal | We 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 resonances | 1969-02 |
233 |
|
Mattis, Daniel C. | Partially frustrated Ising models in two dimensions | We examine ordered, periodic, Ising models on a sq lattice at varying levels x of frustration. The thermodynamic singularity of the fully frustrated model (x=1) is at T=0 while those of partially frustrated lattices (0<x<1) occur at finite Tc . The critical indices in the partially frustrated latti... | Antiferromagnets; Frustration; Ising chain | 2003-06 |
234 |
|
Mishchenko, Eugene | Coulomb drag by small momentum transfer between quantum wires | We 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 liquid | 2003-09 |
235 |
|
Ailion, David Charles | NMR in substitutionally disordered incommensurate (Rb1-xKx)2ZnCl4 | The impurity-concentration dependence of the 8 7Rb NMR line shapes and phason-induced spin-lattice relaxation rates has been studied over a wide temperature range in substitutional^ disordered incommensurate (Rb1_xKJ C)2ZnCl4 for x =0.00, 0.02, and 0.06. The results yield information on the impurity... | NMR; Line shapes; Phasons; Spin-lattice; Phase fluctuations | 1994 |
236 |
|
Mattis, Daniel C. | Steady-state distribution function in dilute electron gases | It is usually assumed that optically created carriers in a photoconductor rapidly thermalize to a Boltzmann distribution, regardless of the generation and recombination mechanisms. However, it can be shown that this distribution which is characteristic of thermodynamic equilibrium is incompatible w... | Photoconductors; Thermal scattering; Steady state; Cyclotron resonance | 1960-10 |
237 |
|
Vardeny, Zeev Valentine | Laser action in conducting polymers | We discuss both cooperative radiation and stimulated emission and consider their role in spectral narrowing of luminescent conducting polymers. We argue that cooperative radiation is favored in films with poor optical confinement. On the other hand, directional stimulated emission can be observed in... | Laser action; Cooperative radiation; Stimulated emission; PPV; Disubstituted polyacetylene; Excitons; Spectral narrowing; Plastic lasers; Superfluorescence; Microcavity lasers | 1997 |
238 |
|
DeTar, Carleton | Thermodynamics with 2+1 and 3 flavors of improved staggered quarks | We present preliminary results 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_2s a2, a4 Symanzik improved gauge action and an order _x0... | Staggered quarks | 2002-05 |
239 |
|
Wu, Yong-Shi | Ground states and thermal states of the random field Ising model | The random field Ising model is studied numerically at both zero and positive temperature. Ground states are mapped out in a region of random field and external field strength. Thermal states and thermodynamic properties are obtained for all temperatures using the Wang-Landau algorithm. The specific... | Ground states; Thermal states | 2005-09 |
240 |
|
Vardeny, Zeev Valentine | Optical studies of ordered and disordered α-sexithiophene films | We have studied α-sexithiophene (α-6T) films by photoinduced absorption (PA) and optically-detected magnetic resonance (ODMR). The PA of the disordered film is composed of two polaron PA bands and one bipolaron PA band, each with its own vibronic side bands. Measurements of an ordered film indicat... | Optically detected magnetic resonance; Sexithiophene conjugated oligomer | 1997 |
241 |
|
Williams, Clayton C. | Single-electron manipulation to and from a SiO2 surface by electrostatic force microscopy | Occupation of individual electron states near the surface of a SiO2 film is controlled by reversible single-electron tunneling to or from a metallic electrostatic force microscope probe. By switching the polarity of an applied dc bias between the probe and the sample to adjust the Fermi energy of ... | | 2005 |
242 |
|
Saam, Brian; Laicher, Gernot | Nuclear spin relaxation of 129Xe due to persistent xenon dimers | We have measured longitudinal nuclear relaxation rates of 129Xe in Xe-N2 mixtures at densities below 0.5 amagats in a magnetic field of 8.0 T. We find that intrinsic spin relaxation in this regime is principally due to fluctuations in the intramolecular spin-rotation (SR) and chemical-shift-anisot... | Nuclear spin relaxation; Xe129; Xenon dimmers | 2006-12 |
243 |
|
Ailion, David Charles | NMR determination of the Edwards-Anderson order parameter in the deuterated pseudo-spin glass Rb1-x(ND4)xD2PO4: anisotropy and concentration dependence of the ND4 deuteron second moment | We measured the rotationally averaged N D 4 + deuteron second moment in deuterated mixed single crystals Rb1_x(ND4 ) xD2P04 with x = 0.22, 0.44, 0.78, and pure ND4D2P04 . We found that the linewidths of the mixed systems show a strong dependence on the crystal's orientation with respect to the exter... | NMR; Crystals; Deuteron second moment; Anisotropy; Linewidth | 1990 |
244 |
|
Symko, Orest George | Noise characteristics and instabilities of long Josephson junctions | In a magnetic field, current biased long Josephson junctions exhibit the dynamics of fluxon motion which are affected by fluctuations. These consist of telegraph noise at voltage steps and instabilities due to chaotic behavior. Results on long junctions with McCumber number fic ranging from 10 to 10... | Fluxon motion; Current biased; Instabilities; Telegraph noise; Perturbed sine-Gordon equation | 1989-03 |
245 |
|
Wu, Yong-Shi | Noncommutative gauge theories in matrix theory | We present a general framework for matrix theory compactified on a quotient space Rn/G, with G a discrete group of Euclidean motions in R". The general solution to the quotient conditions gives a gauge theory on a noncommutative space. We characterize the resulting noncommutative gauge theory in t... | Matrix theory; Noncommutative space | 1998-09 |
246 |
|
Wu, Yong-Shi | Observable effects of the quantum adiabatic phase for noncyclic evolution | It is pointed out that, contrary to naive expectation, the gauge structure or Berry connection recently found in slowly varying quantum systems gives rise to observable effects even for noncyclic evolutions corresponding to open paths in parameter space. We propose to test such effects in muon spin ... | Adiabatic phases; Noncyclic evolution; Eigenstates | 1988-12 |
247 |
|
DeTar, Carleton | Exotic meson spectroscopy from the clover action at β = 5.85 and 6.15* | We repeat our original simulations of the hybrid meson spectrum using the clover action, as a check on lattice artifacts. Our results for the 1−+ masses do not substantially change. We present preliminary results for the wave function of the 1−+ state in Coulomb gauge. | Clover action; Quark spectroscopy | 1999-03 |
248 |
|
Wu, Yong-Shi; Raikh, Mikhail E. | Role of spin-orbit coupling in the metal-insulator transition in two-dimensional systems | We propose an experiment, which would allow us to pinpoint the role of spin-orbit coupling in the metal-nonmetal transition observed in a number of two-dimensional systems at low densities. Namely, we demonstrate that in a parallel magnetic field the interplay between the spin-orbit coupling and the... | Spin-orbit coupling; Metal-insulator transitions | 2000-04 |
249 |
|
DeTar, Carleton | Nature of the thermal phase transition with Wilson quarks | We describe a series of simulations of high temperature QCD with two flavors of Wilson quarks aimed at clarifying the nature of the high temperature phase found in current simulations. Most of our work is with four time slices, although we include some runs with six and eight time slices for compar... | Wilson quarks; Landau gauge; Polyakov loop; Phase transitions | 1994-04 |
250 |
|
Vardeny, Zeev Valentine | Transient and steady-state photoconductivity of a solid C60 film | We report the experimental results of the subnanosecond time-resolved transient photoconductivity (PC) of solid C60 film at various photon energies, and the spectral response of the steady-state PC in the energy range between 1.5 and 4.5 eV. The initial fast transient PC response decays exponenti... | Transient photoconductivity; Steady-state photoconductivity; Solid C60 film | 1993-09 |