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12 December 2008 year (time zone GMT 00:00)  Number of sources in English: 4957
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Frequency-dependent Drude damping in Casimir force calculations. (arXiv:0812.2209v1 [quant-ph])

12.12.2008 12:16    arxiv.org
The Casimir force is calculated between Au thin films that are described by aDrude model with a frequency dependent damping function. The model parametersare obtained from available experimental data for Au thin films. Two cases areconsidered; annealed and nonannealed films
World    Physics    Articles


Entanglement evolution of a two-qubit system with decay beyond rotating-wave approximation. (arXiv:0812.2177v1 [quant-ph])

12.12.2008 12:16    arxiv.org
Two noninteracting atoms, initially entangled in Bell states, are coupled toa one-mode cavity. Based on the reduced non-perturbative quantum masterequation, the entanglement evolution of the two atoms with decay isinvestigated beyond rotating-wave approximation. It is shown that thecounter-rotating wave terms
World    Physics    Articles

Quantum Zeno switch for coherent transport. (arXiv:0812.2151v1 [quant-ph])

12.12.2008 12:16    arxiv.org
Using a dynamical quantum Zeno effect, we propose a general approach tocontrol the coupling between a two-level system (TLS) and its surroundings, bymodulating the energy level spacing of the TLS with a high frequency signal. Weshow that the TLS--surroundings interaction
World    Physics    Articles

Classical spin systems and the quantum stabilizer formalism: general mappings and applications. (arXiv:0812.2127v1 [quant-ph])

12.12.2008 12:16    arxiv.org
We present general mappings between classical spin systems and quantumphysics. More precisely, we show how to express partition functions andcorrelation functions of arbitrary classical spin models as inner productsbetween quantum stabilizer states and product states, thereby generalizingmappings for some specific
World    Physics    Articles


Pull-in control in microswitches using acoustic Casimir forces. (arXiv:0812.2213v1 [quant-ph])

12.12.2008 12:16    arxiv.org
In this paper we present a theoretical calculation of the acoustic Casimirpressure in a model micro system. Unlike the quantum case, the acoustic Casimirpressure can be made attractive or repulsive depending on the frequencybandwidth of the acoustic noise. As a
World    Physics    Articles

The Quantum Locker Puzzle. (arXiv:0812.2242v2 [quant-ph])

12.12.2008 12:16    arxiv.org
The locker puzzle is a game played by multiple players against a referee. Ithas been previously shown that the best strategy that exists cannot succeedwith probability greater than 1-ln2 \approx 0.31, no matter how many playersare involved. Our contribution is
World    Physics    Articles

Casimir Effect for Massless Fermions in One Dimension: A Force Operator Approach. (arXiv:0812.1990v1 [cond-mat.mes-hall] CROSS LISTED)

12.12.2008 12:16    arxiv.org
We calculate the Casimir interaction between two short range scatterersembedded in a background of one dimensional massless Dirac fermions using aforce operator approach. We obtain the force between two finite width squarebarriers, and take the limit of zero width and
World    Physics    Articles

Quantum quenches from integrability: the fermionic pairing model. (arXiv:0812.1928v1 [cond-mat.str-el] CROSS LISTED)

12.12.2008 12:16    arxiv.org
Understanding the non-equilibrium dynamics of extended quantum systems afterthe trigger of a sudden, global perturbation (quench) represents a dauntingchallenge, especially in the presence of interactions. The main difficultiesstem from both the vanishing time scale of the quench event, which can
World    Physics    Articles

Liquid-Drop and Independent-Particle Models Revisited. (arXiv:0812.1469v1 [nucl-th] CROSS LISTED)

12.12.2008 12:16    arxiv.org
Traditionally, the difference in binding energy from the experimental valuewith respect to the theoretical liquid-drop model value, has been seen asindication of independent-particle character along with magicity for particularnumber of protons and neutrons. We study this carefully to demonstrate that
World    Physics    Articles

Effect of a strong laser on spin precession. (arXiv:0812.2110v1 [quant-ph])

12.12.2008 12:16    arxiv.org
The semiclassical dynamics of a charged spin-1/2 particle in an intenseelectromagnetic plane wave is analyzed beyond the electric dipole approximationand taking into account the leading relativistic corrections to the Pauliequation. It is argued that the adiabatic spin evolution driven by
World    Physics    Articles

A dynamic scheme for generating number squeezing in Bose-Einstein condensates through nonlinear interactions. (arXiv:0812.2087v1 [quant-ph])

12.12.2008 12:16    arxiv.org
We develop a scheme to generate number squeezing in a Bose-Einsteincondensate by utilizing interference between two hyperfine levels and nonlinearatomic interactions. We describe the scheme using a multimode quantum fieldmodel and find agreement with a simple analytic model in certain
World    Physics    Articles

Symmetry and the generation and measurement of optical torque. (arXiv:0812.2039v1 [physics.optics])

12.12.2008 12:16    arxiv.org
A key element in the generation of optical torque in optical traps, whichoccurs when electromagnetic angular momentum is transferred from the trappingbeam to the trapped particle by scattering, is the symmetries of the scatteringparticle and the trapping beam. We discuss
World    Physics    Articles

Analysis of Discrete Signals with Stochastic Components using Flicker Noise Spectroscopy. (arXiv:0812.2141v1 [physics.data-an])

12.12.2008 12:16    arxiv.org
The problem of information extraction from discrete stochastic time series,produced with some finite sampling frequency, using flicker-noise spectroscopy,a general framework for information extraction based on the analysis of thecorrelation links between signal irregularities and formulated for continuoussignals, is discussed. It
World    Physics    Articles

Quantum limits in the measurement of very small displacements in optical images. (arXiv:0812.2142v1 [physics.optics])

12.12.2008 12:16    arxiv.org
We consider the problem of the measurement of very small displacements in thetransverse plane of an optical image with a split photodetector. We show thatthe standard quantum limit for such a measurement, which is equal to thediffraction limit divided by
World    Physics    Articles

Off-center defects in crystals revisited: dynamic features. (arXiv:0812.2037v1 [physics.chem-ph])

12.12.2008 12:16    arxiv.org
A survey is presented of the dynamic features of non-itinerant off-centerdefects in crystals, such as rotation-like reorientation of isolated species byeither impurity or host ions. The occurrence of off-center displacements inelectron-vibrational mode systems is regarded as due to the vibronic
World    Physics    Articles

Multiple Parameter Function Approaches to the Equations of Dynamic Convection in a Sea. (arXiv:0812.1831v1 [math-ph] CROSS LISTED)

12.12.2008 12:16    arxiv.org
One of the most important topics in geophysics is to study convection in asea. Based on the algebraic characteristics of the equations of dynamicconvection in a sea, we introduce various schemes with multiple parameterfunctions to solve these equations and obtain
World    Physics    Articles

Spatial Resolution Enhancement in Quantum Imaging beyond the Diffraction Limit Using Entangled Photon-Number State. (arXiv:0812.2032v1 [quant-ph])

12.12.2008 12:16    arxiv.org
In this paper we study the resolution of images illuminated by sourcescomposed of $N+1$ photons in which one non-degenerate photon is entangled with$N$ degenerate photons. The $N$ degenerate photons illuminate an object and arecollected by an $N$ photon detector. The
World    Physics    Articles

Quadratic-Argument Approach to the Davey-Stewartson Equations. (arXiv:0812.1833v1 [math-ph] CROSS LISTED)

12.12.2008 12:16    arxiv.org
The Davey-Stewartson equations are used to describe the long time evolutionof a three-dimensional packets of surface waves. Assuming that the argumentfunctions are quadratic in spacial variables, we find in this paper variousexact solutions modulo the most known symmetry transformations for
World    Physics    Articles

Stabilization of two-dimensional solitons and vortices against supercritical collapse by lattice potentials. (arXiv:0812.1924v1 [nlin.PS] CROSS LISTED)

12.12.2008 12:16    arxiv.org
It is known that optical-lattice (OL) potentials can stabilize solitons andsolitary vortices against the critical collapse, generated by the cubicattractive nonlinearity in the 2D geometry. We demonstrate OLs can alsostabilize various species of fundamental and vortical solitons against thesuper-critical collapse,
World    Physics    Articles

Optimization of Decentralized Scheduling for Physic Applications in Grid Environments. (arXiv:0812.2164v1 [cs.DC])

12.12.2008 12:16    arxiv.org
This paper presents a scheduling framework that is configured for, and usedin physic systems. Our work addresses the problem of scheduling variouscomputationally intensive and data intensive applications that are required forextracting information from satellite images. The proposed solution allowsmapping of
World    Physics    Articles

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