1
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Di Paola C, Gianturco FA, López-Durán D, de Lara-Castells MP, Delgado-Barrio G, Villarreal P, Jellinek J. Br2(X) Microsolvation in Helium Clusters: Effect of the Interaction on the Quantum Solvent Density Distribution. Chemphyschem 2005; 6:1348-56. [PMID: 15968696 DOI: 10.1002/cphc.200400530] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The Born-Oppenheimer potential energy surface for the Br2(X) molecule interacting with a varying number of 4He bosons is constructed following two different schemes which employ either a full ab initio evaluation of the Br2-He interaction forces or an estimate of the latter through an empirical model. Both descriptions are employed by carrying out diffusion Monte Carlo (DMC) calculations of the ground-state energies and quantum wavefunctions for Br2-(He)n clusters with n up to 24. The results clearly indicate, for both interactions, the occurrence of the full solvation of the molecular dopant within the quantum bosonic "solvent" but also show differences between the two models in terms of the expected density distributions of the surrounding particles within the shorter-range region that makes up the clusters with smaller n values. Our calculations also show that such differences become insignificant for the larger 4He clusters surrounding the Br2 molecule, where density profiles and bulk behaviour are chiefly driven by the solvent structure, once n values reach the region of 15-20 adatoms.
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Affiliation(s)
- Cono Di Paola
- Department of Chemistry and INFM, University of Rome, La Sapienza, Piazzale A. Moro 5, 00185 Rome, Italy
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2
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Alet F, Sørensen ES. Directed geometrical worm algorithm applied to the quantum rotor model. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 68:026702. [PMID: 14525143 DOI: 10.1103/physreve.68.026702] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2003] [Revised: 05/27/2003] [Indexed: 05/24/2023]
Abstract
We discuss the implementation of a directed geometrical worm algorithm for the study of quantum link-current models. In this algorithm the Monte Carlo updates are made through the biased reptation of a worm through the lattice. A directed algorithm is an algorithm where, during the construction of the worm, the probability for erasing the immediately preceding part of the worm, when adding a new part, is minimal. We introduce a simple numerical procedure for minimizing this probability. The procedure only depends on appropriately defined local probabilities and should be generally applicable. Furthermore, we show how correlation functions C(r,tau) can be straightforwardly obtained from the probability of a worm to reach a site (r,tau) away from its starting point independent of whether or not a directed version of the algorithm is used. Detailed analytical proofs of the validity of the Monte Carlo algorithms are presented for both the directed and undirected geometrical worm algorithms. Results for autocorrelation times and Green's functions are presented for the quantum rotor model.
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Affiliation(s)
- Fabien Alet
- Computational Laboratory, ETH Zürich, CH-8092 Zürich, Switzerland.
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3
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Alet F, Sørensen ES. Cluster Monte Carlo algorithm for the quantum rotor model. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 67:015701. [PMID: 12636557 DOI: 10.1103/physreve.67.015701] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2002] [Indexed: 05/24/2023]
Abstract
We propose a highly efficient "worm"-like cluster Monte Carlo algorithm for the quantum rotor model in the link-current representation. We explicitly prove detailed balance for the algorithm even in the presence of disorder. For the pure quantum rotor model with mu=0, the algorithm yields high- precision estimates for the critical point K(c)=0.333 05(5) and the correlation length exponent nu=0.670(3). For the disordered case, mu=1 / 2+/-1 / 2, we find nu=1.15(10).
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Affiliation(s)
- Fabien Alet
- Laboratoire de Physique Quantique and UMR 5626, Université Paul Sabatier, 31062 Toulouse, France
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4
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Da Costa G, Parra JE, Mosqueda F. Laser-induced migration of oil particles suspended in a water matrix. APPLIED OPTICS 2002; 41:6420-6430. [PMID: 12396195 DOI: 10.1364/ao.41.006420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The thermoconvective flow induced in oil samples and oil-in-water emulsions by irradiation with a laser beam is studied experimentally. The samples are irradiated by He-Ne and CO2 lasers at different power levels. Time-resolved records of temperature and surface waves that propagate in a liquid surface are presented. In laser-heated emulsions the thermoconvective flow leads the dispersed oil droplets to the water-free surface where they agglomerate to form a floating oil layer. The reflected light beam is formed by a speckle pattern whose intensity and contrast show a spiking, quasi-periodic time variation. A theoretical model is proposed to explain this phenomenon.
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Affiliation(s)
- German Da Costa
- Departamento de Física, Universidad Simón Bolivar, Caracas, Venezuela.
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5
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Rokhinson LP, Guo LJ, Chou SY, Tsui DC, Eisenberg E, Berkovits R, Altshuler BL. Coherent electron transport in a Si quantum dot dimer. PHYSICAL REVIEW LETTERS 2002; 88:186801. [PMID: 12005708 DOI: 10.1103/physrevlett.88.186801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2001] [Indexed: 05/23/2023]
Abstract
We show that the coherence of charge transfer through a weakly coupled double-dot dimer can be determined by analyzing the statistics of the conductance pattern, and does not require a large phase coherence length in the host material. We present an experimental study of the charge transport through a small Si nanostructure, which contains two quantum dots. The transport through the dimer is shown to be coherent. At the same time, one of the dots is strongly coupled to the leads, and the overall transport is dominated by inelastic cotunneling processes.
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Affiliation(s)
- L P Rokhinson
- Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA
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6
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Abstract
The Hubbard on-site repulsion U between opposite spin electrons on the same atomic orbital is widely regarded to be the most important source of electronic correlation in solids. Here we extend the Hubbard model to account for the fact that the experimentally measured atomic U is different from the one obtained by calculation of the atomic Coulomb integral. The resulting model describes quasiparticles that become increasingly dressed as the number of electrons in the band increases. Superconductivity can result in this model through quasiparticle undressing. Various signatures of this physics in spectroscopies in the normal and superconducting states are discussed. A novel effect in the normal state is predicted to be electroluminescence at the sample-positive counterelectrode boundary.
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Affiliation(s)
- J E Hirsch
- Department of Physics, University of California-San Diego, La Jolla, California 92093-0319, USA
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7
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Dagan Y, Deutscher G. Doping and magnetic field dependence of in-plane tunneling into YBa(2)Cu(3)O(7-x): possible evidence for the existence of a quantum critical point. PHYSICAL REVIEW LETTERS 2001; 87:177004. [PMID: 11690297 DOI: 10.1103/physrevlett.87.177004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2000] [Indexed: 05/23/2023]
Abstract
We present tunneling measurements into (1,1,0) YBa(2)Cu(3)O(7-x) films at various doping levels around the optimum. We find that, above a certain doping level near optimum doping, a spontaneous zero bias conductance peak splitting, delta, appears. It increases with doping. It also increases with magnetic field applied along the c axis, for both underdoped and overdoped films. The low field susceptibility chi = d delta /dH/(H-->0) is maximum, possibly diverging when the spontaneous value of delta goes to zero. These results suggest a transition from a pure d(x(2)-y(2)) to a d+id(xy) or d+is order parameter.
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Affiliation(s)
- Y Dagan
- School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, 69978 Tel Aviv, Israel
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8
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Keller M, Metzner W, Schollwöck U. Dynamical mean-field theory for pairing and spin gap in the attractive hubbard model. PHYSICAL REVIEW LETTERS 2001; 86:4612-4615. [PMID: 11384296 DOI: 10.1103/physrevlett.86.4612] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2000] [Indexed: 05/23/2023]
Abstract
We solve the attractive Hubbard model for arbitrary interaction strengths within dynamical mean-field theory. We compute the transition temperature for superconductivity and analyze electron pairing in the normal phase. The normal state is a Fermi liquid at weak coupling and a non-Fermi-liquid state with a spin gap at strong coupling. Away from half filling, the quasiparticle weight vanishes discontinuously at the transition between the two normal states.
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Affiliation(s)
- M Keller
- Theoretische Physik C, Technische Hochschule Aachen, D-52056 Aachen, Germany
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9
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Clerk AA, Waintal X, Brouwer PW. Fano resonances as a probe of phase coherence in quantum dots. PHYSICAL REVIEW LETTERS 2001; 86:4636-4639. [PMID: 11384302 DOI: 10.1103/physrevlett.86.4636] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2000] [Indexed: 05/23/2023]
Abstract
In the presence of direct trajectories connecting source and drain contacts, the conductance of a quantum dot may exhibit resonances of the Fano type. Since Fano resonances result from the interference of two transmission pathways, their line shape (as described by the Fano parameter q) is sensitive to dephasing in the quantum dot. We show that under certain circumstances the dephasing time can be extracted from a measurement of q for a single resonance. We also show that q fluctuates from level to level, and we calculate its probability distribution for a chaotic quantum dot. Our results are relevant to recent experiments by Göres et al. [Phys. Rev. B 62, 2188 (2000)].
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Affiliation(s)
- A A Clerk
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
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10
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Mirlin AD, Wölfle P. Comment on "Antilocalization in a 2D electron gas in a random magnetic field". PHYSICAL REVIEW LETTERS 2001; 86:3688-3689. [PMID: 11328056 DOI: 10.1103/physrevlett.86.3688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2000] [Indexed: 05/23/2023]
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11
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Andreev AV, Matveev KA. Coulomb blockade oscillations in the thermopower of open quantum dots. PHYSICAL REVIEW LETTERS 2001; 86:280-283. [PMID: 11177811 DOI: 10.1103/physrevlett.86.280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2000] [Indexed: 05/23/2023]
Abstract
We consider Coulomb blockade oscillations of thermoelectric coefficients of a single electron transistor based on a quantum dot strongly coupled to one of the leads. An analytic expression for the thermopower as a function of temperature T and the reflection amplitude r in the quantum point contact is obtained. Two regimes can be identified: T<<EC/r/2 and T>>EC/r/2, where EC is the charging energy of the dot. The former regime is characterized by a weak logarithmic dependence of the thermopower on the reflection coefficient, in the latter the thermopower is linear in the reflection coefficient /r/2 but depends on temperature only logarithmically.
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Affiliation(s)
- A V Andreev
- Department of Physics, University of Colorado, Boulder 80309, USA
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12
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Albrecht C, Smet JH, Weiss D, Umansky V, Schweizer H. Evidence of Hofstadter's Fractal Energy Spectrum in the Quantized Hall Conductance. PHYSICAL REVIEW LETTERS 2001; 86:147-150. [PMID: 11136115 DOI: 10.1103/physrevlett.86.147] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2000] [Indexed: 05/23/2023]
Abstract
The energy spectrum of a two-dimensional electron system in a perpendicular homogeneous magnetic field and a weak lateral superlattice potential with square symmetry is composed of Landau bands with recursive internal subband structure. The Hall conductance in the minigaps is anticipated to be quantized in integer multiples of e(2)/h that vary erratically from minigap to minigap in accordance with a Diophantine equation. Hall measurements on samples with the requisite properties uncover this long searched for evidence of Hofstadter's butterflylike energy spectrum.
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Affiliation(s)
- C Albrecht
- Max-Planck-Institut für Festkörperforschung, D-70569 Stuttgart, Germany
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13
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Molodtsov SL, Halilov SV, Servedio VD, Schneider W, Danzenbächer S, Hinarejos JJ, Richter M, Laubschat C. Cooper minima in the photoemission spectra of solids. PHYSICAL REVIEW LETTERS 2000; 85:4184-4187. [PMID: 11056655 DOI: 10.1103/physrevlett.85.4184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2000] [Indexed: 05/23/2023]
Abstract
Variations of the photoionization cross section of valence states as a function of interatomic distance are studied by means of atomic and solid-state density functional approaches and compared with photoemission data. In contrast to the free atom case, a series of Cooper minima is found for 4d, 5d, and 5f states in Pd, Ag, Au, and U metals. The discovered fundamental phenomenon is of high importance for the correct interpretation of photoemission data.
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Affiliation(s)
- S L Molodtsov
- Institut für Oberflächenphysik und Mikrostrukturphysik, TU Dresden, D-01062 Dresden, Germany
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14
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Busse C, Hansen H, Linke U, Michely T. Atomic layer growth on Al(111) by ion bombardment. PHYSICAL REVIEW LETTERS 2000; 85:326-329. [PMID: 10991274 DOI: 10.1103/physrevlett.85.326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2000] [Indexed: 05/23/2023]
Abstract
Instead of the expected erosion morphology composed of craters, rare gas ion bombardment of the Al(111) surface is found to cause initial surface growth of several atomic layers. This phenomenon is observed for Ne+, Ar+, and Xe+ at all temperatures at which bombardment induces morphological surface changes and for ion energies down to a few hundred eV. The effect is interpreted on the basis of a thermal spike induced separation of damage into subsurface vacancy clusters and surface adatom clusters.
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Affiliation(s)
- C Busse
- I. Physikalisches Institut, RWTH Aachen, 52056 Aachen, Germany
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15
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Vedmedenko EY, Oepen HP, Ghazali A, Lévy JC, Kirschner J. Magnetic microstructure of the spin reorientation transition: a computer experiment. PHYSICAL REVIEW LETTERS 2000; 84:5884-5887. [PMID: 10991079 DOI: 10.1103/physrevlett.84.5884] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/1999] [Indexed: 05/23/2023]
Abstract
The scenario of the spin reorientation in two-dimensional films within first-order anisotropy approximation is theoretically studied by means of Monte Carlo simulations. The magnetic microstructure is investigated as a function of the ratio of the perpendicular anisotropy energy to the dipolar one. If the anisotropy dominates, out-of-plane domains will be found while in-plane vortices appear for a vanishing anisotropy. In the range of comparable anisotropy and dipolar energies a complex domain pattern evolves yielding a continuous transition between the two structures. The structure with equally distributed magnetic moment orientations is stable at the point where anisotropy and dipolar energies cancel each other.
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Affiliation(s)
- E Y Vedmedenko
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle, Germany.
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16
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Koch RH, Grinstein G, Keefe GA, Lu Y, Trouilloud PL, Gallagher WJ, Parkin SS. Thermally assisted magnetization reversal in submicron-sized magnetic thin films. PHYSICAL REVIEW LETTERS 2000; 84:5419-5422. [PMID: 10990958 DOI: 10.1103/physrevlett.84.5419] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/1999] [Indexed: 05/23/2023]
Abstract
We have measured the rate of thermally assisted magnetization reversal of submicron-sized magnetic thin films. For fields H just less than the zero-temperature switching field H(C), the probability of reversal, P(exp)(s)(t), increases for short times t, achieves a maximum value, and then decreases exponentially. Micromagnetic simulations exhibit the same behavior and show that the reversal proceeds through the annihilation of two domain walls that move from opposite sides of the sample. The behavior of P(exp)(s)(t) can be understood through a simple "energy-ladder" model of thermal activation.
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Affiliation(s)
- RH Koch
- IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, USA
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17
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Alexandrowicz G, Tashma T, Feintuch A, Grayevsky A, Dormann E, Kaplan N. Spatial mapping of mobility and density of the conduction electrons in (FA)2PF6. PHYSICAL REVIEW LETTERS 2000; 84:2973-2976. [PMID: 11018989 DOI: 10.1103/physrevlett.84.2973] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/1999] [Indexed: 05/23/2023]
Abstract
Novel implementation of the Fourier imaging technique on conduction electron spins in the one-dimensional organic conductors (FA)2PF6 (FA: fluoranthene) is reported. Two-dimensional spatial imaging of resolution 30 &mgr;m(2) is combined with the pulsed-gradient spin-echo technique, to derive maps revealing the local properties of the electron spin density and mobility. The maps generally show pronounced inhomogeneity of both density and mobility on the scale of approximately 30-300 &mgr;m. Highly mobile regions were identified to exist, and the mobility in these was quantitatively evaluated by a basic theoretical model of restricted diffusion.
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Affiliation(s)
- G Alexandrowicz
- Racah Institute of Physics, Hebrew University of Jerusalem, 91904 Jerusalem, Israel
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18
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Petravic M, Deenapanray PN, Comtet G, Hellner L, Dujardin G, Usher BF. Selective photon-stimulated desorption of hydrogen from GaAs surfaces. PHYSICAL REVIEW LETTERS 2000; 84:2255-2258. [PMID: 11017257 DOI: 10.1103/physrevlett.84.2255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/1999] [Indexed: 05/23/2023]
Abstract
Photon-stimulated desorption of H(+) from hydrogenated GaAs (110) and (100) surfaces was studied as a function of photon energy. Distinct peaks, observed around As 3d core-level binding energy for desorption from the GaAs (100) surface and in the As 3d and Ga 3p region for desorption from the GaAs (110) surface, show a striking similarity with the fine structure (spin-orbit splitting) measured in the photoemission from As 3d and Ga 3p levels. These results provide clear evidence for direct desorption processes and represent a basis for selective modification of hydrogenated GaAs surfaces.
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Affiliation(s)
- M Petravic
- Department of Electronic Materials Engineering, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200, Australia
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19
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Gruninger M, Tsvetkov AA, Erb A. Observation of out-of-phase bilayer plasmons in YBa(2)Cu(3)O(7-delta). PHYSICAL REVIEW LETTERS 2000; 84:1575-1578. [PMID: 11017571 DOI: 10.1103/physrevlett.84.1575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/1999] [Indexed: 05/23/2023]
Abstract
The temperature dependence of the c-axis optical conductivity sigma(omega) of optimally and overdoped YBa2Cu3Ox ( x = 6.93 and 7) is reported in the far- (FIR) and midinfrared (MIR) range. Below T(c) we observe a transfer of spectral weight from the FIR not only to the condensate at omega = 0, but also to a new peak in the MIR. This peak is naturally explained as a transverse out-of-phase bilayer plasmon by a model for sigma(omega) which takes the layered crystal structure into account. With decreasing doping the plasmon shifts to lower frequencies and can be identified with the surprising and so far not understood FIR feature reported in underdoped bilayer cuprates.
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Affiliation(s)
- M Gruninger
- Laboratory of Solid State Physics, MSC, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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20
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Benichou O, Cazabat AM, Moreau M, Oshanin G. Stokes formula and density perturbances for driven tracer diffusion in an adsorbed monolayer. PHYSICAL REVIEW LETTERS 2000; 84:511-514. [PMID: 11015951 DOI: 10.1103/physrevlett.84.511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/1999] [Indexed: 05/23/2023]
Abstract
We study the intrinsic friction of monolayers adsorbed on solid surfaces from a gas phase or vapor. Within the framework of the Langmuir model of delocalized adsorption, we calculate the resistance offered by the mobile adsorbate's particles to some impure tracer molecule, whose diffusive random motion is biased by a constant external force. We find that for sufficiently small driving forces the force exerted on the tracer shows viscouslike behavior. We derive then the analog of the Stokes formula for two-dimensional adsorbates, calculate the corresponding friction coefficient, and determine the stationary particle distribution in the monolayer as seen from the driven impurity.
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Affiliation(s)
- O Benichou
- Laboratoire de Physique Theorique des Liquides (CNRS-UMR 7600), Universite Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France
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21
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Nowak U, Chantrell RW, Kennedy EC. Monte carlo simulation with time step quantification in terms of langevin dynamics. PHYSICAL REVIEW LETTERS 2000; 84:163-166. [PMID: 11015860 DOI: 10.1103/physrevlett.84.163] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/1999] [Indexed: 05/23/2023]
Abstract
For the description of thermally activated dynamics in systems of classical magnetic moments numerical methods are desirable. We consider a simple model for isolated magnetic particles in a uniform field with an oblique angle to the easy axis of the particles. For this model, a comparison of the Monte Carlo method with Langevin dynamics yields new insight to the interpretation of the Monte Carlo process, leading to the implementation of a new algorithm where the Monte Carlo step is time quantified. The numeric results for the characteristic time of the magnetization reversal are in excellent agreement with asymptotic solutions for the Neel-Brown model.
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Affiliation(s)
- U Nowak
- Theoretische Tieftemperaturphysik, Gerhard-Mercator-Universitat-Duisburg, 47048 Duisburg, Germany
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22
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Kolomenskii AA, Schuessler HA. Excitation of capillary waves in strongly absorbing liquids by a modulated laser beam. APPLIED OPTICS 1999; 38:6357-6364. [PMID: 18324165 DOI: 10.1364/ao.38.006357] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Several mechanisms for the excitation of capillary waves and for the development of the average deformation of a liquid surface under the action of a modulated laser beam are considered. The amplitude of the capillary wave in a strongly absorbing solution of the dye LDS 751 in ethylene glycol is experimentally studied as a function of laser intensity. Consecutive changes in the predominant mechanism of the excitation with increasing laser intensity are observed and described. At low laser intensities the mechanism connected with the creation of a surface tension gradient prevails. This mechanism becomes nonlinear with increasing influence of the convective motion. In addition, pressure pulsations of the convective flow start to contribute significantly to the generation process. The resonances of capillary waves in a cylindrical container are also investigated and used for determining the surface tension and viscosity of the liquid.
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Affiliation(s)
- A A Kolomenskii
- Department of Physics, Texas A&M University, College Station, Texas 77843-4242, USA.
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23
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Kolomenskii AA, Gershon PD, Schuessler HA. Sensitivity and detection limit of concentration and adsorption measurements by laser-induced surface-plasmon resonance. APPLIED OPTICS 1997; 36:6539-6547. [PMID: 18259515 DOI: 10.1364/ao.36.006539] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The shot noise limitation as well as other factors that influence the sensitivity of measurements with a surface plasmon resonance (SPR) sensor are considered. It is demonstrated that minute changes in the refractive index of a medium close to the surface of a metal film can be detected owing to a shift in the resonance angle. In particular, changes in the adsorption layer of only a fraction of a biomolecular monolayer could be measured. Data for SPR are presented with adjacent media of air, water, as well as aqueous solutions of ethanol and sodium chloride at different concentrations. The immobilization of the protein bovine serum albumin to a specially prepared surface was monitored with the SPR technique. Specific responses to changes in the concentration and thickness of the adsorption layer were determined. The angular resolution of the present apparatus is approximately 1 millidegree, corresponding to a detection limit for an adsorbed protein layer of 15 pg/mm(2), which is still 2 to 3 orders of magnitude larger than the shot-noise limit, and therefore a further improvement in sensitivity is possible.
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24
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Kara A, Durukanoglu S, Rahman TS. Vibrational dynamics and thermodynamics of Ni(977). J Chem Phys 1997. [DOI: 10.1063/1.473309] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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25
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Aryasetiawan F, Gunnarsson O. 3d semicore states in ZnSe, GaAs, and Ge. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:17564-17567. [PMID: 9985880 DOI: 10.1103/physrevb.54.17564] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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26
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Riccardo JL, Steele WA. Molecular dynamics study of tracer diffusion of argon adsorbed on amorphous surfaces. J Chem Phys 1996. [DOI: 10.1063/1.472797] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Esser N, Shkrebtii AI, Resch-Esser U, Springer C, Richter W, Schmidt WG, Bechstedt F. Atomic Structure of the Sb-Stabilized GaAs(100)-(2 x 4) Surface. PHYSICAL REVIEW LETTERS 1996; 77:4402-4405. [PMID: 10062529 DOI: 10.1103/physrevlett.77.4402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Chen Y, Washburn J. Structural Transition in Large-Lattice-Mismatch Heteroepitaxy. PHYSICAL REVIEW LETTERS 1996; 77:4046-4049. [PMID: 10062374 DOI: 10.1103/physrevlett.77.4046] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Tsai M, Jiang JC, Lin SH. pi -bonded-trimer formation on the clean diamond C(111) surface. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:R11141-R11144. [PMID: 9985006 DOI: 10.1103/physrevb.54.r11141] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Koschnick FK, Michael K, Spaeth J, Beaumont B, Gibart P. Optical detection of electron nuclear double resonance on a residual donor in wurtzite GaN. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:R11042-R11045. [PMID: 9984981 DOI: 10.1103/physrevb.54.r11042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Axnäs J, Holm W, Eltsev Y, Rapp Ö. Sign Change of c-Axis Magnetoconductivity in YBa2Cu3O7- delta Single Crystals. PHYSICAL REVIEW LETTERS 1996; 77:2280-2283. [PMID: 10061904 DOI: 10.1103/physrevlett.77.2280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Feibelman PJ, Esch S, Michely T. O Binding Sites on Stepped Pt(111) Surfaces. PHYSICAL REVIEW LETTERS 1996; 77:2257-2260. [PMID: 10061898 DOI: 10.1103/physrevlett.77.2257] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Gudmundsson V, Gerhardts RR. Manifestation of the Hofstadter butterfly in far-infrared absorption. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:R5223-R5226. [PMID: 9986574 DOI: 10.1103/physrevb.54.r5223] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Ihn T, Carmona H, Main PC, Eaves L, Henini M. Magnetic-field-induced resonant tunneling in parallel two-dimensional systems. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:R2315-R2318. [PMID: 9986166 DOI: 10.1103/physrevb.54.r2315] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Calvo V, Lefebvre P, Allègre J, Bellabchara A, Mathieu H, Zhao QX, Magnea N. Evidence of the ordered growth of monomolecular ZnTe islands in CdTe/(Cd,Zn)Te quantum wells on a nominal (001) surface. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:R16164-R16167. [PMID: 9983523 DOI: 10.1103/physrevb.53.r16164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Oepts W, Gijs MA, Reinders A, Jungblut RM. Perpendicular giant magnetoresistance of Co/Cu multilayers on grooved substrates: Systematic analysis of the temperature dependence of spin-dependent scattering. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:14024-14027. [PMID: 9983189 DOI: 10.1103/physrevb.53.14024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Chey SJ, Cahill DG. Dynamics of rough Ge(001) surfaces at low temperatures. PHYSICAL REVIEW LETTERS 1996; 76:3995-3998. [PMID: 10061165 DOI: 10.1103/physrevlett.76.3995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Ranninger J, Robin JM. Manifestations of the pseudogap in the boson-fermion model for Bose-Einstein-condensation-driven superconductivity. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:R11961-R11963. [PMID: 9982898 DOI: 10.1103/physrevb.53.r11961] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Sorensen ES, Roddick E. First-order superconductor-to-insulator transition: Evidence for a supersolid phase. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:R8867-R8870. [PMID: 9982472 DOI: 10.1103/physrevb.53.r8867] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Stumpf R. H-enhanced mobility and defect formation at surfaces: H on Be(0001). PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:R4253-R4256. [PMID: 9984082 DOI: 10.1103/physrevb.53.r4253] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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