Quantum state embezzlement is the transformation |μ〉↦|μ〉|φ〉 using only local operations, where |φ〉 and |μ〉 are multipartite quantum states. Exact embezzlement is an impossible task since it implies the increase of entanglement without communication. Surprisingly, van Dam and Hayden [Phys. Rev. A 67,...

[Phys. Rev. A 90, 042331] Published Fri Oct 24, 2014

]]>We present calculations for the dependence of the two-photon double ionization (DI) of H2 on the relative orientation of the linear laser polarization to the internuclear axis and the length of the pulse. We use the fixed-nuclei approximation at the equilibrium distance of 1.4 a0, where a0=0.529×10−...

[Phys. Rev. A 90, 043416] Published Fri Oct 24, 2014

]]>The existence and stability of domain walls (DWs) and bubble-droplet (BD) states in binary mixtures of quasi-one-dimensional ultracold Bose gases with inter- and intraspecies repulsive interactions is considered. Previously, DWs were studied by means of coupled systems of Gross-Pitaevskii equations ...

[Phys. Rev. A 90, 043629] Published Fri Oct 24, 2014

]]>We study the cooling performance of a realistic mechanical resonator containing defects. The normal cooling method through an optomechanical system does not work efficiently due to those defects. We show that, by employing periodical σz pulses, we can eliminate the interaction between defects and th...

[Phys. Rev. A 90, 043851] Published Fri Oct 24, 2014

]]>We study the dynamics of a spin ensemble strongly coupled to a single-mode resonator driven by external pulses. When the mean frequency of the spin ensemble is in resonance with the cavity mode, damped Rabi oscillations are found between the spin ensemble and the cavity mode which we describe very a...

[Phys. Rev. A 90, 043852] Published Fri Oct 24, 2014

]]>We consider a microcavity made by a graded-index glass, doped with dye molecules, placed within two planar mirrors and study Bose-Einstein condensation of photons. The presence of the mirrors leads to an effective photon mass, and the index grading provides an effective trapping frequency; the photo...

[Phys. Rev. A 90, 043853] Published Fri Oct 24, 2014

]]>We propose a conditional generation of quantum squeezing from realistic single-photon states. The proposed method does not require any coherent measurement projecting on a superposition of internal levels inside single-photon emitters. Interestingly, the squeezing can be generated despite a low sing...

[Phys. Rev. A 90, 043854] Published Fri Oct 24, 2014

]]>The quantum properties of cold rubidium atoms on a chip can be protected by a thin metal layer on the chip’s surface.

[Phys. Rev. A 90, 040502] Published Thu Oct 23, 2014

]]>We propose an ultrasensitive mass spectrometer based on a coupled quantum-bit-oscillator system. Under dynamical decoupling control of the quantum bit (qubit), the qubit coherence exhibits a comb structure in the time domain. The time-comb structure enables high-precision measurements of oscillator ...

[Phys. Rev. A 90, 042118] Published Thu Oct 23, 2014

]]>We study the dynamics of genuine multipartite entanglement for a system of four qubits. Using a computable entanglement monotone for multipartite systems, we investigate the as yet unexplored aspects of a cavity-reservoir system of qubits. For one specific initial state, we observe a sudden transiti...

[Phys. Rev. A 90, 042330] Published Thu Oct 23, 2014

]]>We derive the analytical expressions for the thermal Casimir-Polder energy and force between a spheroidal nanoparticle above a semi-infinite material and a graphene covered interface. We analyze in detail the Casimir-Polder force between a gold nanoparticle and a single sheet of pristine graphene fo...

[Phys. Rev. A 90, 042510] Published Thu Oct 23, 2014

]]>Ejection of core electrons as a result of recollision in a laser-driven carbon atom is theoretically investigated with a quasiclassical model. The model, called “fermionic molecular dynamics,” gives rise to a ground-state carbon atom where the six electrons are paired in shells, with different bindi...

[Phys. Rev. A 90, 043415] Published Thu Oct 23, 2014

]]>In this work we study the applicability of the local generalized Gibbs ensemble (GGE) to integrable one-dimensional systems with bound states. We find that the GGE, when defined using only local conserved quantities, fails to describe the long-time dynamics for most initial states, including eigenst...

[Phys. Rev. A 90, 043625] Published Thu Oct 23, 2014

]]>In this work we study a quench between a Mott insulator and a repulsive Lieb-Liniger liquid. We explicitly find the stationary state when a long time has passed after the quench. It is given by a generalized Gibbs ensemble (GGE) density matrix, which we completely characterize, calculating the quasi...

[Phys. Rev. A 90, 043626] Published Thu Oct 23, 2014

]]>We study phase diffusion in a Bose–Einstein condensate of light in a dye-filled optical microcavity, i.e., the spreading of the probability distribution for the condensate phase. To observe this phenomenon, we propose an interference experiment between the condensed photons and an external laser. We...

[Phys. Rev. A 90, 043627] Published Thu Oct 23, 2014

]]>We consider bosons in a Hubbard lattice with an SU(N) pseudospin degree of freedom which is made dynamical via a coherent transfer term. It is shown that, in the basis which diagonalizes the pseudospin coupling, a generic hopping process affects the spin state, similarly to a spin-orbit coupling. Th...

[Phys. Rev. A 90, 043628] Published Thu Oct 23, 2014

]]>The contribution to the ionization cross section of ionization-excitation processes by electron impact is usually negligibly small for low- and medium-Z elements. We demonstrate here, however, that for heavy atomic ions with the outermost shell being nd (n=4,5) the ionization-excitation processes pl...

[Phys. Rev. A 90, 044701] Published Thu Oct 23, 2014

]]>[Phys. Rev. A 90, 049903] Published Thu Oct 23, 2014

]]>We present an ab initio investigation of the below-threshold harmonic generation of helium (He) atoms in few-cycle infrared laser fields by accurately solving the time-dependent Schrödinger equation and Maxwell's equation simultaneously. We find that the enhancement of the below-threshold harmonic g...

[Phys. Rev. A 90, 041401] Published Wed Oct 22, 2014

]]>This paper introduces a theoretical framework for understanding the accumulation of non-Abelian geometric phases in rotating nitrogen-vacancy centers in diamond. Specifically, we consider how degenerate states can be achieved and demonstrate that the resulting geometric phase for multiple paths is n...

[Phys. Rev. A 90, 042116] Published Wed Oct 22, 2014

]]>We derive the Pauli equation for a charged spin particle confined to move on a spatially curved surface S in an electromagnetic field. Using the thin-layer quantization scheme to constrain the particle on S, and in the transformed spinor representations, we obtain the well-known geometric potential ...

[Phys. Rev. A 90, 042117] Published Wed Oct 22, 2014

]]>The existing distributed quantum gates required physical particles to be transmitted between two distant nodes in the quantum network. We here demonstrate the possibility to implement distributed quantum computation without transmitting any particles. We propose a scheme for a distributed controlled...

[Phys. Rev. A 90, 042327] Published Wed Oct 22, 2014

]]>We investigate multipartite entanglement in rings of arbitrary spins with antiferromagnetic interactions between nearest neighbors. In particular, we show that the nondegenerate ground state of rings formed by an even number (N) of spins is N-partite entangled, and exchange energy can thus be used a...

[Phys. Rev. A 90, 042328] Published Wed Oct 22, 2014

]]>Here, we demonstrate that a practical continuous-variable quantum key distribution (QKD) protocol relying on the Gaussian modulation of coherent states features secret key rates that cannot be achieved with standard qubit discrete-variable QKD protocols. Notably, we report a practical postprocessing...

[Phys. Rev. A 90, 042329] Published Wed Oct 22, 2014

]]>The control of multilevel quantum systems is sensitive to implementation errors in the control field and uncertainties associated with system Hamiltonian parameters. A small variation in the control field spectrum or the system Hamiltonian can cause an otherwise optimal field to deviate from control...

[Phys. Rev. A 90, 043414] Published Wed Oct 22, 2014

]]>We study the effects of Rydberg-atom interactions on Autler-Townes (AT) spectra in a dense gas of ultracold cesium atoms. The 6S1/2 and 6P3/2 levels of cesium are strongly coupled (Rabi frequency Ωc), and the resultant AT spectra are probed via excitation into a Rydberg level. Van der Waals interact...

[Phys. Rev. A 90, 043849] Published Wed Oct 22, 2014

]]>Based on the Mie scattering theory and Maxwell stress tensor method, we investigate the transverse optical force (TOF) acting on chiral particles illuminated by a zero-order Bessel beam. It is demonstrated that the particle chirality can induce an azimuthal optical force (AOF), resulting in orbital ...

[Phys. Rev. A 90, 043850] Published Wed Oct 22, 2014

]]>Motivated by a recent experiment by the Ecole Normale Supérieure de Lyon (ENS) group on the mixture of Bose and Fermi superfluids [I. Ferrier-Barbut et al., Science 345, 1035 (2014)10.1126/science.1255380], we investigate the effective scattering between a bosonic atom and a molecule (dimer) of fer...

[Phys. Rev. A 90, 041603] Published Tue Oct 21, 2014

]]>We define a quantum witness for high-mass matter-wave interferometers that allows us to test fundamental assumptions of macroscopic realism. We propose an experimental realization using absorptive laser gratings and show that such systems can strongly violate a macrorealistic quantum-witness equalit...

[Phys. Rev. A 90, 042114] Published Tue Oct 21, 2014

]]>The possibility of state cloning is analyzed in two types of generalizations of quantum mechanics with nonlinear evolution. It is first shown that nonlinear Hamiltonian quantum mechanics does not admit cloning without the cloning machine. It is then demonstrated that the addition of the cloning mach...

[Phys. Rev. A 90, 042115] Published Tue Oct 21, 2014

]]>A big challenge in continuous-variable quantum key distribution is to prove security against arbitrary coherent attacks including realistic assumptions such as finite-size effects. Recently, such a proof has been presented in [Phys. Rev. Lett. 109, 100502 (2012)PRLTAO10.1103/PhysRevLett.109.100502] ...

[Phys. Rev. A 90, 042325] Published Tue Oct 21, 2014

]]>We define and study parafermion stabilizer codes, which can be viewed as generalizations of Kitaev's one-dimensional (1D) model of unpaired Majorana fermions. Parafermion stabilizer codes can protect against low-weight errors acting on a small subset of parafermion modes in analogy to qudit stabiliz...

[Phys. Rev. A 90, 042326] Published Tue Oct 21, 2014

]]>In this work we develop tools that enable the study of nonadiabatic effects with variational and diffusion Monte Carlo methods. We introduce a highly accurate wave-function ansatz for electron-ion systems that can involve a combination of both clamped ions and quantum nuclei. We explicitly calculate...

[Phys. Rev. A 90, 042507] Published Tue Oct 21, 2014

]]>The kinetic-energy distribution of interatomic and -molecular Coulombic decay (ICD) electrons emitted following photoionization of 2s electrons from Ne atoms in NeAr dimers has been measured in a synchrotron radiation experiment with a velocity-map-imaging photoelectron-photoion-coincidence spectrom...

[Phys. Rev. A 90, 042508] Published Tue Oct 21, 2014

]]>At the most fundamental level, the performance of atomic sensors is limited by quantum decoherence. The problem of decoherence has been addressed at low magnetic fields with atomic samples, where the limiting factor of the coherence lifetime arises from spin-exchange collisions. In this paper, we de...

[Phys. Rev. A 90, 042509] Published Tue Oct 21, 2014

]]>A four-body semiclassical model is developed to describe interferences observed in the angular distribution of Auger electrons emitted after double capture in 30-keV He2++H2 collisions. The present model is based on both the corpuscular and wave behaviors of the emitted electron. The corpuscular asp...

[Phys. Rev. A 90, 042711] Published Tue Oct 21, 2014

]]>We present experimental results for dissociative electron attachment to acetylene near the 3 eV 2Πg resonance. In particular, we use an ion-momentum imaging technique to investigate the dissociation channel leading to C2H− fragments. From our measured ion-momentum results we extract fragment kinetic...

[Phys. Rev. A 90, 042712] Published Tue Oct 21, 2014

]]>We investigate the superfluid phase transition and single-particle excitations in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover regime of an unpolarized ultracold Fermi gas with mass imbalance (where two different species contributing to Cooper pairs have different a...

[Phys. Rev. A 90, 043622] Published Tue Oct 21, 2014

]]>We consider the ground state of a bilayer system of dipolar bosons, where dipoles are oriented by an external field in the direction perpendicular to the parallel planes. Quantum Monte Carlo methods are used to calculate the ground-state energy, the one-body and two-body density matrix, and the supe...

[Phys. Rev. A 90, 043623] Published Tue Oct 21, 2014

]]>We theoretically study magnetic properties of two-component cold fermions in half-filled multilayer Lieb optical lattices, i.e., two, three, and several layers, using the dynamical mean-field theory. We clarify that the magnetic properties of this system become quite different depending on whether t...

[Phys. Rev. A 90, 043624] Published Tue Oct 21, 2014

]]>We propose to engineer the quantum state in a high-dimensional Hilbert space by taking advantage of a χ(2)-modulated nonlinear waveguide array. By varying the pump condition and the waveguide array length, the momentum correlation between the signal and idler photons can be manipulated, exhibiting b...

[Phys. Rev. A 90, 043842] Published Tue Oct 21, 2014

]]>A detailed theoretical investigation is performed for the self-compression of relativistically strong laser pulses under plasma wake wave excitation conditions. An analytical expression is obtained for the characteristic length of laser pulse self-compression in the one-dimensional case. A good agre...

[Phys. Rev. A 90, 043843] Published Tue Oct 21, 2014

]]>We suggest the generation of photon pairs in a thermally induced nonlinear periodically poled silica fiber by spontaneous parametric down-conversion. Photons are generated directly in eigenstates of optical angular momentum. Photons in a pair can be entangled in these states as well as in frequencie...

[Phys. Rev. A 90, 043844] Published Tue Oct 21, 2014

]]>We describe theoretically the process of spontaneous parametric down-conversion in quadratic nonlinear waveguide arrays in the presence of linear loss. We derive a set of discrete Schrödinger-type equations for the biphoton wave function and the wave function of one photon when the other photon in a...

[Phys. Rev. A 90, 043845] Published Tue Oct 21, 2014

]]>We theoretically demonstrate second-order Talbot effect (SOTE) based on entangled photon pairs. The photon pairs are generated from the spontaneous parametric four-wave mixing (SPFWM) process in a cold atomic medium and can be taken as the imaging light in order to realize coincidence recording. A s...

[Phys. Rev. A 90, 043846] Published Tue Oct 21, 2014

]]>We theoretically investigate mode broadening of a high-Q optical whispering-gallery microcavity coupled to a single or multiple dielectric or plasmonic subwavelength particles. The result shows that backscattering contributes dominantly to the mode broadening in both transmission and reflection spec...

[Phys. Rev. A 90, 043847] Published Tue Oct 21, 2014

]]>Optomechanics allows the transduction of weak forces to optical fields, with many efforts approaching the standard quantum limit. We consider force sensing in a mirror-in-the-middle optomechanical setup and use two coupled cavity modes originated from normal mode splitting for separating pump and pr...

[Phys. Rev. A 90, 043848] Published Tue Oct 21, 2014

]]>We investigate the dissipative influence of environmental fluctuations on the dynamics of driven quantum systems at an avoided crossing. We derive two simple approximative equations valid for weak system-bath coupling and compare results for the dissipative Landau-Zener problem with numerically exac...

[Phys. Rev. A 90, 042112] Published Mon Oct 20, 2014

]]>Heisenberg's uncertainty principle is quantified by error-disturbance tradeoff relations, which have been tested experimentally in various scenarios. Here we shall report various error-disturbance tradeoff relations by decomposing the measurement errors and disturbance into two different components,...

[Phys. Rev. A 90, 042113] Published Mon Oct 20, 2014

]]>We propose a method for deterministic generation of entanglement between a quantum-dot spin and a photon. Entanglement is established by an elastic scattering event from a cavity that is strongly coupled to a singly charged quantum dot. Due to the elastic nature of the interaction, the energy of the...

[Phys. Rev. A 90, 042322] Published Mon Oct 20, 2014

]]>We study the H3×N hybrid entanglement between charge and vibrational modes in a triple-quantum-dot shuttle system. Three quantum dots are linearly connected, with the outer dots fixed and the central dot oscillating, described as a quantum harmonic oscillator with oscillation modes that are entangle...

[Phys. Rev. A 90, 042323] Published Mon Oct 20, 2014

]]>We consider systems of two and three qubits, mutually coupled by Heisenberg-type exchange interaction and interacting with external laser fields. We show that these systems allow one to create maximally entangled Bell states, as well as three-qubit Greenberger-Horne-Zeilinger and W states. In partic...

[Phys. Rev. A 90, 042324] Published Mon Oct 20, 2014

]]>A theoretical model of the influence of detection bandwidth properties on observed line shapes in laser absorption spectroscopy is described, thereby predicting artificial frequency shifts, extra broadenings, and line asymmetries which must be taken into account in order to obtain accurate line parameters.

[Phys. Rev. A 90, 042506] Published Mon Oct 20, 2014

]]>We develop a theoretical framework for the quasi-low-dimensional confinement-induced resonances (CIRs) of particles with three-dimensional two-body interactions describable by the Huang-Yang pseudopotential. Using this approach, we analytically obtain the universal properties of dipolar CIRs in quas...

[Phys. Rev. A 90, 042710] Published Mon Oct 20, 2014

]]>We show that Jaynes-Cummings dynamics can be observed in mesoscopic atomic ensembles interacting with a classical electromagnetic field in the regime of a Rydberg blockade where the time dynamics of the average number of Rydberg excitations in mesoscopic ensembles displays collapses and revivals typ...

[Phys. Rev. A 90, 043413] Published Mon Oct 20, 2014

]]>We study a spin-orbit (SO)-coupled hyperfine spin-1 Bose-Einstein condensate (BEC) in a quasi-one-dimensional trap. For an SO-coupled BEC in a one-dimensional box, we show that in the absence of the Rabi term, any nonzero value of SO coupling will result in a phase separation among the components fo...

[Phys. Rev. A 90, 043619] Published Mon Oct 20, 2014

]]>A two-dimensional Bose-Einstein condensate (BEC) split by a radial potential barrier is investigated. We determine on an accurate many-body level the system's ground-state phase diagram as well as a time-dependent phase diagram of the splitting process. Whereas the ground state is condensed for a wi...

[Phys. Rev. A 90, 043620] Published Mon Oct 20, 2014

]]>The collective excitations of a zero-temperature, spin-polarized, harmonically trapped, two-dimensional dipolar Fermi gas are examined within the Thomas-Fermi–von Weizsäcker hydrodynamic theory. We focus on repulsive interactions and investigate the dependence of the excitation frequencies on the st...

[Phys. Rev. A 90, 043621] Published Mon Oct 20, 2014

]]>A light-matter interaction modified by the material environment is one of the central topics in quantum electrodynamics. While a strong coupling between a single emitter and a cavity and the Markovian (exponential) relaxation regime are most straightforwardly covered by theory, real physical systems...

[Phys. Rev. A 90, 043836] Published Mon Oct 20, 2014

]]>We show how interference effects are responsible for manipulating the output electromagnetic field of an optical microresonator in the good-cavity limit. The system of interest consists of a moderately strongly pumped two-level emitter embedded in the optical cavity. When an additional weaker laser ...

[Phys. Rev. A 90, 043837] Published Mon Oct 20, 2014

]]>The resonant quantum dynamics of an excited two-level emitter is investigated via classical modulation of its transition frequency while simultaneously the radiator interacts with a broadband electromagnetic field reservoir. The frequency of modulation is selected to be of the order of the bare-stat...

[Phys. Rev. A 90, 043838] Published Mon Oct 20, 2014

]]>We propose a scheme to efficiently manipulate optomechanical systems into and out of chaotic regimes. Here the optical system is coherently driven by a continuous-wave bichromatic laser field consisting of a pump field and a probe field, where the beat frequency of the bichromatic components plays a...

[Phys. Rev. A 90, 043839] Published Mon Oct 20, 2014

]]>Quantum optomechanics offers the potential to investigate quantum effects in macroscopic quantum systems in extremely well-controlled experiments. In this paper we discuss one such situation, the dynamic stabilization of a mechanical system such as an inverted pendulum. The specific example that we ...

[Phys. Rev. A 90, 043840] Published Mon Oct 20, 2014

]]>One-way quantum computing uses single-qubit projective measurements performed on a cluster state (a highly entangled state of multiple qubits) in order to enact quantum gates. The model is promising due to its potential scalability; the cluster state may be produced at the beginning of the computati...

[Phys. Rev. A 90, 043841] Published Mon Oct 20, 2014

]]>Quantum spin chains may be used to transfer quantum states between elements of a quantum information processing device. A scheme discovered recently [Phys. Rev. A 85, 022312 (2012)PLRAAN10.1103/PhysRevA.85.022312] was shown to have favorable transfer properties for single-qubit states even in the pr...

[Phys. Rev. A 90, 044301] Published Mon Oct 20, 2014

]]>Spontaneous parametric down-conversion (SPDC) in a nonlinear crystal generates two single photons (signal and idler) with random phases. Thus, no first-order interference between them occurs. However, coherence can be induced in a cascaded setup of two crystals if, e.g., the idler modes of both crys...

[Phys. Rev. A 90, 045803] Published Mon Oct 20, 2014

]]>We contribute to a long-standing debate on the supposed failure of the fluctuation dissipation theorem (FDT) for the Davies master equation (DME), an important class of Lindblad quantum master equations, describing time-driven quantum systems weakly coupled to a heat bath. First we propose two simpl...

[Phys. Rev. A 90, 042110] Published Fri Oct 17, 2014

]]>We study the (2 + 1)-dimensional Dirac oscillator in a homogeneous magnetic field in the noncommutative plane. It is shown that the effect of noncommutativity is twofold: (i) momentum noncommuting coordinates simply shift the critical value (Bcr) of the magnetic field at which the well known left-ri...

[Phys. Rev. A 90, 042111] Published Fri Oct 17, 2014

]]>We study the x-ray emission following the collision of a Bi83+ ion with a neutral Xe atom at the projectile energy 70 MeV/u. The collisional and post-collisional processes are treated separately. The probabilities of various many-electron processes at the collision are calculated within a relativist...

[Phys. Rev. A 90, 042709] Published Fri Oct 17, 2014

]]>We present measurements of resistive and sympathetic cooling of ion clouds confined in a Penning trap. For resistive cooling of a cloud consisting of one ion species, we observe a significant deviation from exponential cooling behavior which is explained by an energy-transfer model. The observed sym...

[Phys. Rev. A 90, 043412] Published Fri Oct 17, 2014

]]>We study the evolution of correlations in a quasi-two-dimensional dipolar gas driven out of equilibrium by a sudden ramp of the interactions. On short time scales, rotonlike excitations coherently oscillate in and out of the condensate, giving rise to pronounced features in the time evolution of the...

[Phys. Rev. A 90, 043617] Published Fri Oct 17, 2014

]]>With the aid of numerical simulations, the phase diagram of ultracold bosonic atoms in optical lattices can be reconstructed using a quantum nondemolition measurements based on the quantum Faraday effect.

[Phys. Rev. A 90, 043618] Published Fri Oct 17, 2014

]]>On the basis of the Maxwell-Lorentz local-field equations and nonlocal linear response theory, a self-consistent microscopic Green function theory of diffraction of light from a single hole in a thin and plane metallic screen is established. By subtracting the scattering of identical incident fields...

[Phys. Rev. A 90, 043830] Published Fri Oct 17, 2014

]]>We consider how a single photon can probe the quantum nature of a moving mirror in the context of quantum optomechanics. In particular, we demonstrate how the single-photon time-dependent spectrum reveals the time required for the fully resolved spectrum to build up as a result of the single photon ...

[Phys. Rev. A 90, 043831] Published Fri Oct 17, 2014

]]>We employ a quasimode representation of the adjoint master equation to study nonlinear pair-generation dynamics via spontaneous four-wave mixing in coupled-cavity systems in the presence of scattering loss. Perturbative analytic solutions for signal and idler photon-number operators are derived, whi...

[Phys. Rev. A 90, 043832] Published Fri Oct 17, 2014

]]>We study mode properties in multimode optical waveguides with parity-time (PT) symmetry. We find that two guiding modes with successive orders 2m−1 and 2m form a mode pair in the sense that the two components of the pair evolve into the same mode when the loss and gain coefficient increases to some ...

[Phys. Rev. A 90, 043833] Published Fri Oct 17, 2014

]]>In this paper we investigate the propagation of an intense linearly polarized laser through an ionizing gaseous medium in the presence of an axial strong magnetic field, addressing the modulation of laser polarization. Our simulation indicates that the laser polarization can be dramatically modulate...

[Phys. Rev. A 90, 043834] Published Fri Oct 17, 2014

]]>We demonstrate the stabilization of an unstable steady state in an optomechanical system for low and high pump rates. The optomechanical system consists of a pumped cavity with one movable mirror. The stabilization is achieved by applying Pyragas control, i.e., feeding back the cavity field by an ex...

[Phys. Rev. A 90, 043835] Published Fri Oct 17, 2014

]]>We derive a general approximate solution to the problem of minimizing the conditional entropy of a qudit-qubit system resulting from a local measurement on the qubit, which is valid for general entropic forms and becomes exact in the limit of weak correlations. This entropy measures the average cond...

[Phys. Rev. A 90, 042318] Published Thu Oct 16, 2014

]]>Quantum technology promises revolutionary advantages in information processing and transmission compared to classical technology; however, determining which specific resources are needed to surpass the capabilities of classical machines often remains a nontrivial problem. To address such a problem, ...

[Phys. Rev. A 90, 042319] Published Thu Oct 16, 2014

]]>For any N⊗N-type bipartite system with even N>2, two-parameter continuous families of unital block-dephasing quantum channels and of weakly optimal entanglement witnesses are constructed from special forms of a parametrized positive map. The parameter domains of the families are complementary sub...

[Phys. Rev. A 90, 042320] Published Thu Oct 16, 2014

]]>Adiabatic quantum computation, based on the adiabatic theorem, is a promising alternative to conventional quantum computation. The validity of an adiabatic algorithm depends on the existence of a nonzero energy gap between the ground and excited states. However, it is difficult to ascertain the exac...

[Phys. Rev. A 90, 042321] Published Thu Oct 16, 2014

]]>We present electronic stopping power data for H and He ions in Zn and In obtained from backscattering experiments in the range of low velocities; for In data are obtained up to the stopping maximum. These results in combination with previous data are analyzed to unravel the influence of d electrons ...

[Phys. Rev. A 90, 042706] Published Thu Oct 16, 2014

]]>We explore the three-body problem in two dimensions using the adiabatic hyperspherical representation. We develop the main equations in terms of democratic hyperangular coordinates and determine several symmetry properties and boundary conditions for both interacting and noninteracting solutions. Fr...

[Phys. Rev. A 90, 042707] Published Thu Oct 16, 2014

]]>Stationary afterglow measurements in conjunction with near-infrared absorption spectroscopy show that the recombination of the H3+ ion with electrons in ionized gas mixtures of He, Ar, and H2 at 300 K is strongly enhanced by neutral helium and by molecular hydrogen. The H2-assisted ternary recombina...

[Phys. Rev. A 90, 042708] Published Thu Oct 16, 2014

]]>We predict the effect of the roton instability for a two-dimensional weakly interacting gas of tilted dipoles in a single homogeneous quantum layer. Being typical for strongly correlated systems, the roton phenomena appear to occur in a weakly interacting gas. It is important that in contrast to a s...

[Phys. Rev. A 90, 043616] Published Thu Oct 16, 2014

]]>We present a microscopic model of cavity quantum electrodynamics based on a one-dimensional (1D) coupled cavity array (CCA), where a supercavity (SC) is composed by a segment of the 1D CCA with relatively smaller couplings with the outsides. The single-photon scattering problem for the SC empty or w...

[Phys. Rev. A 90, 043828] Published Thu Oct 16, 2014

]]>Conservation of spin angular momentum in high-harmonic generation is probed using bichromatic counter-rotating high-intensity laser pulses.

[Phys. Rev. A 90, 043829] Published Thu Oct 16, 2014

]]>A method to dynamically decouple the effects of two-body atom-atom interactions for ultracold bosonic atoms and realize a system dominated by three-body interactions is presented, which is useful for a number of applications such as the possible realization of novel three-body phases and states.

[Phys. Rev. A 90, 041602] Published Wed Oct 15, 2014

]]>Adiabatic transport provides a powerful way to manipulate quantum states. By preparing a system in a readily initialized state and then slowly changing its Hamiltonian, one may achieve quantum states that would otherwise be inaccessible. Moreover, a judicious choice of final Hamiltonian whose ground...

[Phys. Rev. A 90, 042317] Published Wed Oct 15, 2014

]]>Motivated by the remarkable experimental control of synthetic gauge fields in ultracold atomic systems, we investigate the effect of an artificial Rashba spin-orbit coupling on the spin polarization of a two-dimensional repulsive Fermi gas. By using a variational many-body wave function, based on a ...

[Phys. Rev. A 90, 043614] Published Wed Oct 15, 2014

]]>Expressions for the speed and lifetimes of the sound modes in a dilute Bose-Einstein condensate are obtained using Bogoliubov mean field theory. The condensate has two pairs of sound modes which undergo an avoided crossing as the equilibrium temperature is varied. The two pairs of sound modes decay ...

[Phys. Rev. A 90, 043615] Published Wed Oct 15, 2014

]]>We study the far-from-equilibrium statistical mechanics of periodically driven fermionic atoms in a lossy optical resonator. We show that the interplay of the Fermi surface with cavity losses leads to subnatural cavity linewidth narrowing, squeezed light, and nonthermal quantum statistics of the ato...

[Phys. Rev. A 90, 043823] Published Wed Oct 15, 2014

]]>We study an atom-cavity system composed of an ensemble of three-level atoms interacting with a high-finesse single-mode optical resonator. Two examples of physical models, the laser-driven Λ-type atomic system and the three-level ladder-type atomic system, are investigated in detail. By altering the...

[Phys. Rev. A 90, 043824] Published Wed Oct 15, 2014

]]>We study the dynamics of a driven optomechanical cavity coupled to a charged nanomechanical resonator via Coulomb interaction, in which the tunable double optomechanically induced transparency (OMIT) can be observed from the output field at the probe frequency by controlling the strength of the Coul...

[Phys. Rev. A 90, 043825] Published Wed Oct 15, 2014

]]>We capitalize on a multipolar expansion of the polarization density matrix, in which multipoles appear as successive moments of the Stokes variables. When all the multipoles up to a given order K vanish, we can properly say that the state is Kth-order unpolarized, as it lacks of polarization informa...

[Phys. Rev. A 90, 043826] Published Wed Oct 15, 2014

]]>The Talbot effect, i.e., the self-imaging property of a periodic wave in near-field diffraction, is a remarkable interference phenomenon in paraxial systems with continuous translational invariance. In crystals, i.e., systems with discrete translational invariance, self-imaging has been regarded so ...

[Phys. Rev. A 90, 043827] Published Wed Oct 15, 2014

]]>[Phys. Rev. A 90, 049902] Published Wed Oct 15, 2014

]]>The performance of a quantum information processor depends on the precise control of phases introduced into the system during quantum gate operations. As the number of operations increases with the complexity of a computation, the phases of the gates at different locations and different times must b...

[Phys. Rev. A 90, 042316] Published Tue Oct 14, 2014

]]>We study a wide range of neutral atoms and ions suitable for ultraprecise atomic optical clocks with naturally suppressed blackbody-radiation shift of clock transition frequency. Calculations show that scalar polarizabilities of clock states cancel each other for at least one order of magnitude for ...

[Phys. Rev. A 90, 042505] Published Tue Oct 14, 2014

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