Filters: Department: "Physics" School Or College: "College of Science" Collection: "ir_uspace" Format: "application/pdf"
| Creator | Title | Description | Subject | Date | ||
|---|---|---|---|---|---|---|
| 276 |
 |
Mattis, Daniel C. | New wave-operator identity applied to the study of persistent currents in 1D | We show that a large class of backward-scattering matrix elements involving Δk ~ + 2k F vanish for fermions interacting with two-body attractive forces in one dimension. (These same matrix elements are finite for noninteracting particles and infinite for particles interacting with two-body repulsiv... | Persistent current; Supercurrents | 1974 |
| 277 |
 |
Vardeny, Zeev Valentine; Nahata, Ajay | Midinfrared optical response and thermal emission from plasmonic lattices on Al films | We studied the midinfrared optical transmission and thermal light emission spectra of subwavelength hole arrays in the form of square lattice with 4 µm periodicity (plasmonic lattice) in aluminum films deposited on silicon substrates. The optical transmission of these films showed temperature inde... | Plasmonic lattices; Midinfrared optical response; Thermal emission; Surface plasmon polaritons; Anomalous transmission; Extraordinary optical transmission; EOT | 2007-11 |
| 278 |
 |
Sokolsky, Pierre; Cassiday, George L.; Kieda, David B. | Search for y rays above 10^14 eV from Cygnus X-3 during the June and July 1989 radio outbursts | We have looked for γ-ray emission above 100 TeV from the binary x-ray source Cygnus X-3 during a period of intense radio emission in the summer of 1989. We find no evidence for excess air showers from the direction of the source and the muon content of air showers from this direction is the same as... | Cygnus X-3; Radio outbursts; Extensive air showers | 1989-11 |
| 279 |
 |
Mishchenko, Eugene | Breached superfluidity via p-wave coupling | Anisotropic 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 instability | 2005-03 |
| 280 |
 |
DeTar, Carleton | Semileptonic decays of D mesons in three-flavor lattice QCD | We present the first three-flavor lattice QCD calculations for D→ rrlv and D→ Klv semileptonic decays. Simulations are carried out using ensembles of unquenched gauge fields generated by the MILC Collaboration. With an improved staggered action for light quarks, we are able to simulate at light ... | Semileptonic decay; Staggered quarks | 2005-01 |
| 281 |
 |
Vardeny, Zeev Valentine | Picosecond trapping of photocarriers in amorphous silicon | Trapping of photoexcited carriers in the picosecond and subnanosecond time domains was studied by measuring the decay of photoinduced absorption (PA) in a-Si, a-Si:F, a-Si:H, and a-Si:H:F. We found that when the midgap density of states decreases, both the trapping time and its temperature dependenc... | Photocarriers; Amorphous silicon; Picosecond trapping; Photoinduced absorption | 1983 |
| 282 |
 |
Vardeny, Zeev Valentine; Raikh, Mikhail E. | Cooperative emission from a disordered system: a classical model | The 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; Oscillators | 1997 |
| 283 |
 |
Lupton, John Mark | Unraveling the inhomogeneously broadened absorption spectrum of conjugated polymers by single-molecule light-harvesting action spectroscopy | The distribution of chromophores in single polymer chains is revealed by photoluminescence excitation spectroscopy under excitation of the backbone and detection of emission from an end cap. Spectral broadening in excitation exceeds that in emission. An increase in vibronic coupling for shorter (h... | Spectral broadening; Chromophores | 2009-10 |
| 284 |
 |
Kieda, David B.; Sokolsky, Pierre | Search for > 200 TeV photons from Cygnus X-3 in 1988 and 1989 | Over a period of 16 months from April 1988 to August 1989, we have monitored the flux of cosmic-ray showers with energies above 2X 101 4 eV. We used a two-level array of scintillators covering an area of 3 X 104 m2. Counters on the surface measure the size and direction of each shower while counters... | TeV photons; Cosmic ray showers | 1990-07 |
| 285 |
 |
Vardeny, Zeev Valentine | Raman-scattering study of pressure-induced phase transitions in CuI | The pressure-induced phase transitions: zinc-blende (ZB) --* rhombohedral -> tetragonal in Cul were studied by Raman scattering. The rhombohedral primitive cell is presented as a slightly distorted ZB unit cell that is twice as long as the primitive cell in the [111] direction. By folding back the Z... | Raman-scattering; Pressure cell; Phase transitions | 1977-01 |
| 286 |
 |
Vardeny, Zeev Valentine | Optical picosecond studies of carrier thermalization in amorphous silicon | Thermalization of photogenerated hot carriers in a-Si, a-Si:H and a-Si:H:F was studied using the pump and probe method with subpicosecond resolution. The process is optically observable because the absorption cross-section of the hot carriers depends on their excess energy. It was found that the en... | Carrier thermalization; Amorphous silicon; Frohlich interaction | 1981 |
| 287 |
 |
Mishchenko, Eugene; Raikh, Mikhail E. | Penetration of external field into regular and random arrays of nanotubes: implications for field emission | We develop an analytical theory of polarization of a vertically aligned array of carbon nanotubes (NTs) in external electric field. Such arrays are commonly utilized in field-emission devices, due to the known electrostatic effect of strong field enhancement near the tip of an individual NT. A sma... | Field-emission current; Fowler-Nordheim law | 2006-06 |
| 288 |
 |
Vardeny, Zeev Valentine | Photoinduced absorption spectra in amorphous Si:H and Ge:H and microcrystalline Si:H | The steady state subgap photoinduced absorpotion bands in a-Ge:H and a-Si:H are interpreted in terms of two kinds of optical transitions of photoexcited carriers from traps in the gap into the bands of which one produces absorption and the other produces bleaching. The photoinduced absorption in mic... | Photoinduced absorption; Si:H; Ge:H; Amorphous silicon; Amorphous germanium; Microcrystalline silicon | 1984 |
| 289 |
 |
Mattis, Daniel C. | Phonon free path in an isotopic mixture | A time-dependent perturbation theory is developed for the classical laws of motion of a crystal lattice. This is applied to the case of a cubic crystal which is chemically pure but contains various isotopic constituents. The random variations in the masses of neighboring atoms scatter plane wave p... | Crystal lattice; Thermal conductivity | 1957-05 |
| 290 |
 |
Vardeny, Zeev Valentine | Effect of bias illumination on photoinduced absorption decay in ?-Si:H | Zeldov 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 silicon | 1985 |
| 291 |
 |
Ailion, David Charles | 31P NMR spin-lattice relaxation: structural glass dynamics in Rb1-x(ND4)xD2PO4 | We 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-glass | 1993 |
| 292 |
 |
Vardeny, Zeev Valentine; Raikh, Mikhail E. | Emission spectrum of a dipole in a semi-infinite periodic dielectric structure: effect of the boundary | The emission spectrum of a dipole embedded in a semi-infinite photonic crystal is calculated. For simplicity we study the case in which the dielectric function is sinusoidally modulated only along the direction perpendicular to the boundary surface plane. In addition to oscillations of the emission... | Emission spectrum; Dipole; Periodic dielectric structure | 2000-07 |
| 293 |
 |
Wu, Yong-Shi | Implications of a cosmological constant varying as R-2 | We advocate the possibility that the (effective) cosmological constant A varies in time as R- 2, R being the scale factor of our expanding Universe. This behavior can be obtained under some simple and general assumptions in conformity with quantum cosmology. After pointing out several advantages w... | Cosmological constant | 1990-01 |
| 294 |
 |
DeTar, Carleton | Hadronic deformation energy. II. Two-nucleon interaction | The MIT bag model for hadrons is treated in the static cavity approximation. The adiabatic deformation of a six-quark hadron with quantum numbers of the deuteron is studied in a configuration which permits the separation of two triplets with quantum numbers of the neutron and proton. The energy of... | Bag models; Quark bag; Deformation energy; Gluon coupling; Two-nucleon problem; Nucleons; Self-energy | 1978-01 |
| 295 |
 |
Vardeny, Zeev Valentine | Nonlinear optical spectroscopy of excited states in polyfluorene | We used a variety of nonlinear optical (NLO) spectroscopies to study the singlet excited-state order and primary photoexcitations in polyfluorene, an important blue-emitting ∏-conjugated polymer. The polarized NLO spectroscopies include ultrafast pump-probe photomodulation in a broad spectral rang... | pi-conjugated polymers; Polyfluorene; Photoexcitations | 2007-03 |
| 296 |
 |
Vardeny, Zeev Valentine | Stimulated emission in high-gain organic media | Stimulated emission was studied in various scattering gain media, including thin p-conjugated polymer films, organic dyes-doped gel films, and opal crystals saturated with polymer and laser dye solutions. We found that at high excitation intensities a featureless amplified spontaneous emission ban... | Stimulated emission; High-gain organic media; pi-conjugated polymers; Scattering gain media; Organic dyes-doped gel films; Opal crystals | 1999-02 |
| 297 |
 |
Ailion, David Charles | New technique for determining the diffusion mechanism by NMR: application to Cl35 diffusion in TlCl | A major problem in the study of atomic motions is the determination of the dominant mechanism responsible for translational diffusion. Recently Ailion and Ho predicted that the rotating-frame spin-lattice relaxation time T l p would have an angular dependence which depends on the diffusion mechanis... | Diffusion; Solids; NMR | 1972 |
| 298 |
 |
Wu, Yong-Shi | Mott transition in an anyon gas | We introduce and analyze a lattice model of anyons in a periodic potential and an external magnetic field, which exhibits a transition from a Mott insulator to a quantum Hall fluid. The transition is characterized by the anyon statistics a, which can vary between fermions, a = 0, and bosons, ct - 1... | Anyon gas; Periodic potentials; Mott transition | 1993-11 |
| 299 |
 |
DeTar, Carleton | String breaking in lattice QCD | The 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 present simulation results that ... | String breaking; Flux tube; Staggered quarks; Wilson loop; Polyakov loop | 1999-03 |
| 300 |
 |
Mattis, Daniel C. | Ratio 2Δ0/kTc in superconductivity | In high-temperature superconductors, values of the ratio R-2Δ0/kTc have been reported in the range 2-10, whereas low-temperature superconductors rarely deviate by as much as 50% from the BCS prediction R =3.54. Could this variability relate to the density of states near the Fermi surface? Our calcu... | Density of state; Superconductors | 1991-12 |