You've searched: Department: "Physics" Collection: "ir_uspace"
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1 Gerton, JordanImproved localization accuracy in stochastic super-resolution fluorescence microscopy by K-factor image deshadowingLocalization of a single fluorescent particle with sub-diffraction-limit accuracy is a key merit in localization microscopy. Existing methods such as photoactivated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM) achieve localization accuracies of single emitt...2014-01-01
2 Mattis, Daniel C.Conductivity of one-dimensional interacting fermions*Using an exactly soluble model, the decay rate of a current-carrying state of one-dimensional fermions is calculated in the presence of random scatterers at finite temperature and the dc conductivity thereby inferred. For interacting fermions it is modified by a factor (T/T + θ)g, where g is a posi...Fermi gas1974-04
3 DeTar, CarletonLeptonic decay constants fDs and fD in three flavor lattice QCDWe determine the leptonic decay constants fDs and fD in three flavor unquenched lattice QCD. We use O(a2)-improved staggered light quarks and O(a)-improved charm quarks in the Fermilab heavy quark formalism. Our preliminary results, based upon an analysis at a single lattice spacing, are fDs = 263+5...Decay constants2005-03
4 Bromley, Benjamin C.Periodic standing-wave approximation: nonlinear scalar fields, adapted corrdinates, and the eigenspectral methodThe periodic standing wave (PSW) method for the binary inspiral of black holes and neutron stars computes exact numerical solutions for periodic standing-wave spacetimes and then extracts approximate solutions of the physical problem, with outgoing waves. The method requires solution of a boundary-...Periodic standing wave method; Black holes; Neutron stars2005
5 Vardeny, Zeev ValentineOrganic spin-valves: physics and applicationsSpin-valve devices of organic semiconductors in the vertical configuration using a variety of exotic and regular ferromagnetic electrodes were fabricated and studied as a function of applied magnetic field, temperature and applied bias voltage. These devices show that spin polarized carriers can be ...Organic spin-valves; Spin-polarized transport; Spin-polarized carrier injection; Spin polarization2005
6 Wu, Yong-ShiManifestations of Berry's topological phase for the photonRecently, Berry recognized in quantum mechanics a topological phase factor arising from the adiabatic transport of a system around a closed circuit, which is essentially the Aharonov-Bohm effect in parameter space. Here we consider manifestations of this phase factor for a photon in a state of adia...Aharonov-Bohm effect; Optical fibers; Waveguide1986-08
7 DeTar, CarletonTopological susceptibility in staggered fermion chiral perturbation theoryThe topological susceptibility of the vacuum in quantum chromodynamics has been simulated numerically using the Asqtad improved staggered fermion formalism. At nonzero lattice spacing, the residual fermion doublers (fermion tastes) in the staggered fermion formalism give contributions to the suscept...Staggered fermions; Chiral perturbation2004-10
8 Wu, Yong-ShiMatrix compactification on orientifoldsGeneralizing previous results for orbifolds, in this paper we describe the compactification of the matrix model on an orientifold which is a quotient space Rd/G as a Yang-Mills theory residing on a quantum space. The information of the compactification is encoded in the action of the discrete symmet...Spacetime; Orientifolds; Compactification; Quantum space1999-06
9 Wu, Yong-ShiExplicit solutions of the Bethe ansatz equations for Bloch electrons in a magnetic fieldFor Bloch electrons in a magnetic field, explicit solutions are obtained at the center of the spectrum for the Bethe ansatz equations of Wiegmann and Zabrodin. When the magnetic flux per plaquette is 1/(Q with Q an odd integer, distribution of the roots of the Bethe ansatz equation is uniform except...Bloch electron; Magnetic flux1994-08
10 Williams, Clayton C.Advances in experimental technique for quantitative two dimensional dopant profiling by scanning capacitance microscopySeveral advances have been made toward the achievement of quantitative two-dimensional dopant and carrier profiling. To improve the dielectric and charge properties of the oxide-silicon interface, a method of low temperature heat treatment has been developed which produces an insulating layer with c...Doping; Scanning capacitance microscope; SCM1999
11 Wu, Yong-ShiTwisted supersymmetric invariant formulation of Chern-Simons gauge theory on a latticeWe propose a twisted supersymmetric (SUSY) invariant formulation of the Chern-Simons theory on a Euclidean three-dimensional lattice. The SUSY algebra to be realized on the lattice is the N ¼ 4 D ¼ 3 twisted algebra that was recently proposed by D'Adda et al. In order to keep the manifest anti-Her...Twisted supersymmetry; Chern-Simons gauge theory2008-09
12 Ailion, David CharlesNuclear magnetic resonance in random fields: cluster formation and local dynamics of a deuteron glassNMR data show that the deuteron "pseudo spin-glass" transition in Rbi- X(ND4)*D2P04 is not just a simple kinetic slowing down process but is characterized by a gradual condensation of randomly polarized clusters as expected if we deal with a percolation transition in eigenstate space. The results pr...NMR; Nuclear magnetic resonance; Random fields; Spin lattice1986
13 Gondolo, PaoloDark Stars: the first stars in the universe may be powered by dark matter healingA new line of research on Dark Stars is reviewed, which suggests that the first stars to exist in the universe were powered by dark matter heating rather than by fusion. Weakly Interacting Massive Particles, which may be there own antipartmers, collect inside the first stars and annihilate to produc...Dark stars; WIMP; Weakly interacting massive particles2009
14 Williams, Clayton C.Sub-10 nm lateral spatial resolution in scanning capacitance microscopy achieved with solid platinum probesSub-10 nm resolution can be obtained in scanning capacitance microscopy (SCM) if the probe tip is approximately of the same size. Such resolution is observed, although infrequently, with present commercially available probes. To acquire routine sub-10 nm resolution, a solid Pt metal probe has bee...2004
15 Mishchenko, EugeneGapless surfaces in anisotropic superfluidsWe demonstrate when p-wave pairing occurs between species whose free Fermi surfaces are mismatched the gap generally vanishes over a two-dimensional surface. We present detailed calculations of condensation energy, superfluid density (Meissner mass) and specific heat for such states. We also consi...Anisotropic superfluids; Meissner mass2006-11
16 Gondolo, PaoloNeutralino dark matter vs galaxy formationNeutralino dark matter may be incompatible with current cold dark matter models with cuspy dark halos, because excessive synchrotron radiation may originate from neutralino annihilations close to the black hole at the galactic center.Neutralinos; Cuspy dark halos2000
17 Vardeny, Zeev ValentinePhotoexcitation dynamics in polyacetylene probed by transient photoinduced resonant Raman scatteringWe have measured photoexcitation dynamics in the picosecond time domain in fully trans and partially isomerized (CH)X and (CD)X films with different cis/trans content ratios, using the technique of transient photoinduced resonant Raman scattering. Following the distinctively different decay kineti...Photoexcitation dynamics1992-05
18 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Classification of disorder and extrinsic order in polymers by resonant Raman scatteringResonant Raman scattering is used to quantify the effect of disorder and extrinsic order on Peierls systems such as (CH)X . We introduce "X plots" in which the phonon and gap distribution are related and characterize the system by the functional dependence of the gap 2 A on the coupling X. For c/s-r...Peierls systems1985-01
19 Wu, Yong-ShiIdentification of androgen response elements in the insulin-like growth factor I upstream promoterTestosterone stimulates the expression of IGF-I in cells and tissues that include prostate, muscle and muscle satellite cells, and the uterus. Here, the molecular mechanisms of this effect of testosterone were explored. Testosterone increased IGF-I mRNA levels in HepG2 and LNCaP cells and stimulated...IFG-I; Androgen-responsive elements2007
20 DeTar, CarletonFirst signs for string breaking in two-flavor QCDWe have been examining the phenomenon of string breaking in QCD with two flavors of dynamical staggered quarks. We construct a transfer matrix from a combination of "string" and "two-meson" channels. Preliminary results with low statistics show the expected signs of string breaking.String breaking; Wilson loop; Staggered quarks2000-04
21 Symko, Orest GeorgeContinuously operating 4He evaporation refrigeratorA simple and compact device was developed to provide continuous, self-regulating refrigeration at approximately 1.3 K. The temperature of the device remains nearly constant, independent of external power, up to a critical power. For a molar flow rate of 10^-4 moles/sec, the refrigerator can absorb...4He evaporation refrigerator1971
22 DeTar, CarletonTopological susceptibility with the improved Asqtad actionChiral perturbation theory predicts that in quantum chromodynamics light dynamical quarks suppress the topological (instanton) susceptibility.We investigate this suppression through direct numerical simulation using the Asqtad improved lattice fermion action. This action holds promise for carrying...Chiral perturbation; Staggered fermions2003-12
23 Ailion, David CharlesLow cost integrated circuit versatile pulse and frequency counterIn this paper we describe a compact multipurpose counter whose design is based on the use of plastic integrated circuits. The circuit contains about $90 worth of semiconductor components and is very easy to wire; nevertheless, it is extremely versatile. It consists of dual 107 and 106 counters which...Integrated circuits; Counters; Physics instruments1969
24 Vardeny, Zeev ValentineStudies of picosecond carrier dynamics in polysilane alloys: evidence for geminate recombination in small hydrogenated amorphous silicon clustersThe ultrafast photocarrier dynamics in polysilane alloys amorphous (SiH2)n' has been studied using the picosecond photoinduced absorption (PA) technique. For excitation below the optical gap, the PA response decays exponentially and is faster at low temperatures. This is interpreted in terms of e-h ...Picosecond carrier dynamics; Polysilane alloys; Geminate recombination; a-Si:H; Amorphous silicon; Ultrafast relaxation; Photoexcited carriers1990
25 Mishchenko, EugeneSpin Hall edge spin polarization in a ballistic 2D electron systemUniversal properties of the spin Hall effect in ballistic 2D electron systems are addressed. The net spin polarization across the edge of the conductor is second order, ~λ2, in spin-orbit coupling constant independent of the form of the boundary potential, with the contributions of normal and evan...Spin- Hall effect2007-09
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