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CreatorTitleDescriptionSubjectDate
26 Wu, Yong-ShiOpen spin chain and open spinning stringIn this letter, we study the open spinning strings and their SYM duals. A new class of folded open spinning strings is found. At planar one-loop level in SYM, by solving the thermodynamic limit of the Bethe ansatz equations for an integrable open spin chain, we find good agreement with string theory...2004-07
27 Kieda, David B.; Bergman, Douglas R.; Sokolsky, PierreMeasurement of the flux of ultrahigh energy cosmic rays from monocular observations by the high resolution fly's eye experimentWe have measured the cosmic ray spectrum above 10^172 eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode.We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors.We ...High Resolution Fly's Eye; Ultrahigh energy cosmic rays2004-04
28 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
29 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
30 Mishchenko, EugeneOptical conductivity of a two-dimensional electron liquid with spin-orbit interactionThe interplay of electron-electron interactions and spin-orbit coupling leads to a new contribution to the homogeneous optical conductivity of the electron liquid. The latter is known to be insensitive to many-body effects for a conventional electron system with parabolic dispersion. The parabolic...Optical conductivity; Electron liquid; Spin-orbit coupling2006-08
31 Vardeny, Zeev ValentinePicosecond optical time-of-flight studies of carrier transport in α-Si:H/α-SiNx:H multilayersWe report time-of-flight experiments in the time range from 0.2 psec to 1.8 nsec in 0-Si:H-a-SiNx:H multilayer structures using a purely optical technique. The transport mechanism of photoexcited carriers is shown to be dispersive and its characteristic parameters are determined in the temperature r...Time-of-flight; Amorphous silicon; Carrier transport; Photoexcited carriers1987-09
32 Mattis, Daniel C.Theory of paramagnetic impurities in semiconductorsIn this paper, a model of a paramagnetic impurity in a semiconductor (or of an F' center in an alkali halide) is proposed. It is an exactly soluble form of the quantum-mechanical 3-body problem. Specifically, we deal with 2 interacting particles in any number of dimensions in an attractive external ...Paramagnetic impurities; Eigenstates1966
33 Mishchenko, EugeneFrequency dependence of the photonic noise spectrum in an absorbing or amplifying diffusive mediumA theory is presented for the frequency dependence of the power spectrum of photon current fluctuations originating from a disordered medium. Both the cases of an absorbing medium ("grey body") and of an amplifying medium ("random laser") are considered in a waveguide geometry. The semiclassical ap...Random laser; Noise power spectrum; Frequency dependence; Waveguide geometry2001-01
34 Gerton, JordanSinglet s-wave scattering lengths of 6Li and 7LiPhotoassociation of ultracold lithium atoms into bound vibrational levels of the A 1Σu+ excited state is used to probe the X1Σg+ ground-state interaction potential of 6Li2 and 7Li2 . It had been predicted that the s-wave photoassociation signal strength would pass through a minimum as a function...1996-06
35 Gerton, JordanTip-enhanced fluorescence microscopy at 10 nanometer resolutionWe demonstrate unambiguously that the field enhancement near the apex of a laser-illuminated silicon tip decays according to a power law that is moderated by a single parameter characterizing the tip sharpness. Oscillating the probe in intermittent contact with a semiconductor nanocrystal strongly...2004-10
36 Lupton, John MarkLinewidth-limited energy transfer in single conjugated polymer moleculesUsing low temperature single molecule spectroscopy on rigid-rod conjugated polymers we are able to identify homogeneously broadened, strongly polarized emission from individual chromophore units on a single chain. Gated fluorescence spectroscopy allows real time imaging of intramolecular energy tran...Linewidth-limited; Energy transfer; Rigid-rod; Single molecule spectroscopy; Gated fluorescence spectroscopy; Chromophores; Intramolecular energy transfer; Spectral linewidth2003-12
37 Kieda, David B.Overview of the ANITA projectThe ANITA project is designed to investigate ultra-high energy (>1017 eV) cosmic ray interactions throughout the universe by detecting the neutrinos created in those interactions. These high energy neutrinos are detectable through their interactions within the Antarctic ice sheet, which ANITA will u...ANITA; Antarctic Impulsive Transient Antenna; High energy neutrinos; Antarctica; Balloon2003
38 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
39 Symko, Orest GeorgeMagnetic anisotropy of Zn-Cr alloys at very low temperaturesThe temperature dependent magnetization of Zn-Cr single crystals was measured from 2K down to 10 mK using a SQUID magnetometer. A large anisotropy is observed for the magnetization along the parallel and perpendicular axes of the crystal. For low concentrations impurity-impurity reactions do not do...Magnetic anisotropy; Zn-Cr alloys; Temperature dependent magnetization1978
40 Vardeny, Zeev ValentineOptically-detected magnetic-resonance study of triplet state dynamics in C70We present studies of fluorescence, phosphorescence, photoinduced absorption, and their respective optically detected magnetic resonance of C70 molecules dispersed in polystyrene glasses. Two distinct triplet excitons are identified with principle zero-field splitting parameters (D≈0.0089 and 0.0...Ttriplet state dynamics; C70; Polystyrene glasses1996-03
41 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
42 Mishchenko, Eugene; Raikh, Mikhail E.Zero-bias tunneling anomaly in a clean 2D electron gas caused by smooth density variationsWe show that smooth variations, δn(r), of the local electron concentration in a clean 2D electron gas give rise to a zero-bias anomaly in the tunnel density of states, v(ω), even in the absence of scatterers, and thus, without the Friedel oscillations. The energy width, ω0, of the anomaly scale...Tunnel density of states; Disordered metals2007-11
43 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
44 Vardeny, Zeev ValentineTransient spectroscopy of Frenkel and charge transfer excitons in α-sexithienyl filmsPhotoexcitations dynamics are investigated in a-sexithienyl nanocrystalline films using transient photomodulation in a spectral range from 0.4 to 2.5 eV and time domain from 200 fs to 50 ms. We identify intrachain and interchain excitations. The former are even parity excitons with ultrafast dynami...Transient spectroscopy; Excitons; Frenkel exciton; Charge transfer exciton; Transient photomodulation1997-10
45 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Photomodulation spectroscopy of iodine-doped polyacetylene; phase transition from soliton lattice to metalUsing the photomodulation technique for iodine I3-)-doped polyacetylene, we have found spectroscopic evidence for an abrupt phase transition at 5% I3-. The transition is from the lightly doped phase best described as soliton lattice to the heavily doped metallic phase. The phase transition is chara...Photomodulation spectroscopy; Iodine-doped polyacetylene1986-10
46 Vardeny, Zeev ValentinePlastic microring lasers on fibers and wiresPhotopumped, pulsed, narrow line laser emission is demonstrated using cylindrical microcavities formed by p-conjugated polymer thin films wrapped around thin glass optical fibers and metal wires with various diameters D. A variety of cavity-dependent resonant laser mode structures were observed, whi...Microring lasers; pi-conjugated polymers; pi-conjugated polymer thin films; Microcavities1998
47 Vardeny, Zeev ValentineOptical bias control of dispersive relaxations in α-Si:HRelaxation of the photoinduced ir absorption band in α-Si:H was studied in the microsecond time domain as a function of cw bias illumination. The decays follow a power law t-α where the dispersion parameter a increases with bias illumination. At low temperatures, a increases linearly with the st...Optical bias control; Dispersive relaxations; a-Si:H; Amorphous silicon1984-01
48 Mattis, Daniel C.New mapping for particles on lattices with hard-core interactionsA novel mapping between Hilbert spaces of unequal dimensionalities yields many-body states which exactly satisfy the no-double-occupancy constraints for particles on lattices in arbitrary spatial dimensions. After proving the states are complete, we apply them to Nagaoka's theorem and the t-J model...Ferromagnetism; Spin; Dimensions1996
49 Symko, Orest GeorgeMicrowave absorption in the superconducting and normal phases of Y-Ba-Cu-OMicrowave absorption in a dc magnetic field up to 12 kG, attributed to nonequilibrium contributions to the ac susceptibility, appears at Tc as the sample is cooled. ESR measurements of YBa-Cu-O show that Cu2+ exists only in the fraction of the sample which is not superconducting in a distorted octa...Microwave absorption; Superconducting phase; YBCO; High Tc1987-08
50 Wu, Yong-ShiRemarks on noncommutative open string theory: V duality and holographyIn this paper we study the interplay of electric and magnetic backgrounds in determining the decoupling limit of coincident D branes towards a noncommutative Yang-Mills (NCYM) or open string (NCOS) theory. No decoupling limit has been found for the NCYM model with space-time noncommutativity. It i...Hubbard operator; Bosonization; Deformation; t-J model2001-03
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