Quantum entanglement lies at the heart of quantum mechanics and quantum information processing. In this work, we show a framework where entangled states play the role of witnesses. We extend the notion of entanglement witnesses, developing a hierarchy of witnesses for classes of observables. This hi...

[Phys. Rev. A 97, 050302(R)] Published Fri May 25, 2018

]]>Photoionization microscopy (PM) is an experimental method allowing for high-resolution measurements of the electron current probability density in the case of photoionization of an atom in an external uniform static electric field. PM is based on high-resolution velocity-map imaging and offers the u...

[Phys. Rev. A 97, 053412] Published Fri May 25, 2018

]]>We present a detailed analysis of the effects of photon statistics on multiphoton ionization. Through a detailed study of the role of intermediate states, we evaluate the conditions under which the premise of nonresonant processes is valid. The limitations of its validity are manifested in the depen...

[Phys. Rev. A 97, 053413] Published Fri May 25, 2018

]]>Interaction-based readout protocols that may provide rapid, quantum-enhanced metrology are studied by employing twist-and-turn dynamics. Such metrology is expected to be robust to detection noise and may optimally utilize the entanglement of a quantum state.

[Phys. Rev. A 97, 053618] Published Fri May 25, 2018

]]>We report on a systematic study of temporal Kerr cavity soliton dynamics in the presence of pulsed or amplitude-modulated driving fields. In stark contrast to the more extensively studied case of phase modulations, we find that Kerr cavity solitons are not always attracted to maxima or minima of dri...

[Phys. Rev. A 97, 053834] Published Fri May 25, 2018

]]>We analyze the second-order photon autocorrelation function ${g}^{\left(2\right)}$ with respect to the photon probability distribution and discuss the generic features of a distribution that results in superthermal photon bunching [${g}^{\left(2\right)}\left(0\right)>2$]. Superthermal photon bunching has been reported for a number of optical ...

[Phys. Rev. A 97, 053835] Published Fri May 25, 2018

]]>The electron impact $X{\phantom{\rule{0.16em}{0ex}}}^{1}{\mathrm{\Sigma}}_{g}^{+}\to b{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{\Sigma}}_{u}^{+}$ transition in molecular hydrogen is one of the most important dissociation pathways to forming atomic hydrogen atoms, and is of great importance in modeling astrophysical and industrial plasmas where molecular hydrogen is a substantial constituent. Recently, it has be...

[Phys. Rev. A 97, 050702(R)] Published Thu May 24, 2018

]]>Finding the solutions of the equations that describe the dynamics of a given physical system is crucial in order to obtain important information about its evolution. However, by using estimation theory, it is possible to obtain, under certain limitations, some information on its dynamics. The quantu...

[Phys. Rev. A 97, 052125] Published Thu May 24, 2018

]]>The time evolution of periodically driven non-Hermitian systems is in general nonunitary but can be stable. It is hence of considerable interest to examine the adiabatic following dynamics in periodically driven non-Hermitian systems. We show in this work the possibility of *piecewise* adiabatic follo...

[Phys. Rev. A 97, 052126] Published Thu May 24, 2018

]]>Quantum networks are an integral component in performing efficient computation and communication tasks that are not accessible using classical systems. A key aspect in designing an effective and scalable quantum network is generating entanglement between its nodes, which is robust against defects in...

[Phys. Rev. A 97, 052325] Published Thu May 24, 2018

]]>This paper deals with a channel-parameter estimation for continuous-variable quantum key distribution (CV-QKD) over a satellite-to-submarine link. In particular, we focus on the channel transmittances and the excess noise which are affected by atmospheric turbulence, surface roughness, zenith angle ...

[Phys. Rev. A 97, 052326] Published Thu May 24, 2018

]]>As shown by Einstein, Podolsky, and Rosen (the EPR paradox) [A. Einstein, B. Podolsky, and N. Rosen, Phys. Rev. **47**, 777 (1935)], quantum mechanics is a nonlocal theory contrarily to what happens for any other modern physical theory. Alternative local theories based on superluminal communications hav...

[Phys. Rev. A 97, 052124] Published Wed May 23, 2018

]]>Corrections to the Lamb shift are calculated for hydrogenlike ions to all orders in the nuclear binding-strength parameter, where the numerical accuracy is improved by one order of magnitude over previous calculations.

[Phys. Rev. A 97, 052509] Published Wed May 23, 2018

]]>We present an experimental and theoretical study of photoelectron momentum distributions for nitric oxide (NO) and carbon monoxide (CO) molecules generated by intense linearly polarized laser pulses. It is shown that the measured distributions along the outermost backward rescattering caustic are we...

[Phys. Rev. A 97, 053411] Published Wed May 23, 2018

]]>We study an array of two-level systems arranged on a lattice and illuminated by an external plane wave which drives a dipolar transition between the two energy levels. In this setup, the two-level systems are coupled by dipolar interactions and subject to nonlocal dissipation, and so behave as an op...

[Phys. Rev. A 97, 053616] Published Wed May 23, 2018

]]>We generalize the Beliaev diagrammatic theory of an interacting spinless Bose-Einstein condensate to the case of a binary mixture. We derive a set of coupled Dyson equations and find analytically the Green's functions of the system. The elementary excitation spectrum consists of two branches, one of...

[Phys. Rev. A 97, 053617] Published Wed May 23, 2018

]]>This paper aims to explicitly clarify the role and interpretation of diamagnetic interactions between molecules and light in quantum electrodynamics. In contrast to their electric and magnetic counterparts, the diamagnetic couplings between light and matter have received relatively little interest i...

[Phys. Rev. A 97, 053832] Published Wed May 23, 2018

]]>We obtain general analytic expressions for the linear and angular momentum density of an elliptically polarized paraxial laser beam. As a partial case, we obtain expressions for the linear and angular momentum density of a paraxial elliptically polarized optical vortex. It is shown that for an arbit...

[Phys. Rev. A 97, 053833] Published Wed May 23, 2018

]]>[Phys. Rev. A 97, 059905] Published Wed May 23, 2018

]]>Quantifying the degree of irreversibility of an open system dynamics represents a problem of both fundamental and applied relevance. Even though a well-known framework exists for thermal baths, the results give diverging results in the limit of zero temperature and are also not readily extended to n...

[Phys. Rev. A 97, 052123] Published Tue May 22, 2018

]]>We experimentally realize and theoretically analyze narrow-band biphotons generated in a hot rubidium vapor cell by four-wave-mixing processing. A dressing laser beam is used to alternate both linear and nonlinear susceptibilities of the vapor, thereby modifying the biphoton's temporal correlation f...

[Phys. Rev. A 97, 053830] Published Tue May 22, 2018

]]>Single- and two-mode multiphoton states are the cornerstone of many quantum technologies, e.g., metrology. In the optical regime, these states are generally obtained combining heralded single photons with linear optics tools and post-selection, leading to inherent low success probabilities. In a rec...

[Phys. Rev. A 97, 053831] Published Tue May 22, 2018

]]>We present a mathematical framework based on quantum interval-valued probability measures to study the effect of experimental imperfections and finite precision measurements on defining aspects of quantum mechanics such as contextuality and the Born rule. While foundational results such as the Koche...

[Phys. Rev. A 97, 052121] Published Mon May 21, 2018

]]>In the conventional two-point measurement scheme of quantum thermodynamics, quantum coherence is destroyed by the first measurement. But as we know the coherence really plays an important role in the quantum thermodynamics process, and how to describe the work statistics for a quantum coherent proce...

[Phys. Rev. A 97, 052122] Published Mon May 21, 2018

]]>We investigate the performance of discrimination strategy in the comparison task of known quantum states. In the discrimination strategy, one infers whether or not two quantum systems are in the same state on the basis of the outcomes of separate discrimination measurements on each system. In some c...

[Phys. Rev. A 97, 052323] Published Mon May 21, 2018

]]>We report a measurement of the lifetime of the cesium $7s\phantom{\rule{0.16em}{0ex}}{}^{2}S_{1/2}$ state using time-correlated single-photon counting spectroscopy in a vapor cell. We excite the atoms using a Doppler-free two-photon transition from the $6s\phantom{\rule{0.16em}{0ex}}{}^{2}S_{1/2}$ ground state, and detect the $1.47-\mu \mathrm{m}$ photons from the spontaneous decay of th...

[Phys. Rev. A 97, 052507] Published Mon May 21, 2018

]]>We analyze in detail how the interplay between electronic structure and cluster geometry determines the stability and the fragmentation channels of single Pd-doped cationic Au clusters, $\mathrm{PdA}{\mathrm{u}}_{N}{}_{-1}{}^{+}$ ($N=2-20$). For this purpose, a combination of photofragmentation experiments and density functional theory...

[Phys. Rev. A 97, 052508] Published Mon May 21, 2018

]]>Electron transfer processes in ${\mathrm{He}}^{+}+\mathrm{He}$ collisions are studied theoretically using a three-electron semiclassical atomic-orbital close-coupling method in a wide energy domain, from 1 to 225 keV/u. Total, state-selective, and angular-differential cross sections are presented and compared with available...

[Phys. Rev. A 97, 052709] Published Mon May 21, 2018

]]>Under the self-consistent mean-field approach for the BCS-BEC crossover problem, we derive a closed-form analytical expression for the general spin response of noncentrosymmetric Fermi superfluids with arbitrary spin-orbit coupling and Zeeman fields. In addition to the paramagnetic, i.e., the Pauli ...

[Phys. Rev. A 97, 053613] Published Mon May 21, 2018

]]>Experimental control over ultracold quantum gases has made it possible to investigate low-dimensional systems of both bosonic and fermionic atoms. In closed one-dimensional systems there are many similarities in the dynamics of local quantities for spinless fermions and strongly interacting “hard-co...

[Phys. Rev. A 97, 053614] Published Mon May 21, 2018

]]>We study statistical properties of $N$ noninteracting identical bosons or fermions in the canonical ensemble. We derive several general representations for the $p$-point correlation function of occupation numbers $\overline{{n}_{1}\cdots {n}_{p}}$. We demonstrate that it can be expressed as a ratio of two $p\times p$ determinants involvin...

[Phys. Rev. A 97, 053615] Published Mon May 21, 2018

]]>Control over the spectral properties of the bright squeezed vacuum (BSV), a highly multimode nonclassical macroscopic state of light that can be generated through high-gain parametric down conversion, is crucial for many applications. In particular, in several recent experiments BSV is generated in ...

[Phys. Rev. A 97, 053827] Published Mon May 21, 2018

]]>We propose a model of a slow surface plasmon-polariton distributed-feedback laser with pump by drift current. The amplification in the dielectric–semiconducting film–dielectric waveguide structure is created by fast drift current in the graphene layer, placed at the semiconductor/dielectric interfac...

[Phys. Rev. A 97, 053828] Published Mon May 21, 2018

]]>We show that it is possible to realize simultaneous Raman lasing at two different frequencies using a double-$\mathrm{\Lambda}$ system pumped by a bifrequency field. The bifrequency Raman lasers are phase-locked to one another and the beat-frequency matches the energy difference between the two metastable ground sta...

[Phys. Rev. A 97, 053829] Published Mon May 21, 2018

]]>In the study of quantum nonlocality, one obstacle is that the analytical criterion for identifying the boundaries between quantum and postquantum correlations has not yet been given, even in the simplest Bell scenario. We propose a plausible, analytical, necessary and sufficient condition ensuring t...

[Phys. Rev. A 97, 050102(R)] Published Fri May 18, 2018

]]>Open quantum systems exhibit a range of novel out-of-equilibrium behavior due to the interplay between coherent quantum dynamics and dissipation. Of particular interest in these systems are driven, dissipative transitions, the emergence of dynamical phases with novel broken symmetries, and critical ...

[Phys. Rev. A 97, 052116] Published Fri May 18, 2018

]]>We present a method to detect topological invariants in nonunitary parity-time-symmetric (PT-symmetric) quantum walks (QWs). The topological phases of a PT-symmetric QW can be characterized by the mean position of the walk, which is an experimentally observable quantity. This method can also be appl...

[Phys. Rev. A 97, 052117] Published Fri May 18, 2018

]]>Collapse models postulate that space is filled with a collapse noise field, inducing quantum Brownian motions, which are dominant during the measurement, thus causing collapse of the wave function. An important manifestation of the collapse noise field, if any, is thermal energy generation, thus dis...

[Phys. Rev. A 97, 052118] Published Fri May 18, 2018

]]>We discuss limits on the noise strength parameter in mass-proportional-coupled wave-function collapse models implied by bulk heating effects and examine the role of the noise power spectrum in comparing experiments of different types. This comparison utilizes a calculation of the rate of heating thr...

[Phys. Rev. A 97, 052119] Published Fri May 18, 2018

]]>We analyze in full detail the time evolution of an open Gaussian quantum system rapidly bombarded by Gaussian ancillae. As a particular case this analysis covers the thermalization (or not) of a harmonic oscillator coupled to a thermal reservoir made of harmonic oscillators. We derive general result...

[Phys. Rev. A 97, 052120] Published Fri May 18, 2018

]]>We demonstrate subpicosecond-timescale population transfer between the pair of hyperfine ground states of atomic rubidium using a single laser-pulse. Our scheme utilizes the geometric and dynamic phases induced during Rabi oscillation through the fine-structure excited state to construct an $X$ rotati...

[Phys. Rev. A 97, 052322] Published Fri May 18, 2018

]]>In the experimental determination of the population transfer efficiency between discrete states of a coherently driven quantum system it is often inconvenient to measure the population of the target state. Instead, after the interaction that transfers the population from the initial state to the tar...

[Phys. Rev. A 97, 053409] Published Fri May 18, 2018

]]>The concept of the potential-energy surface (PES) and directional reaction coordinates is the backbone of our description of chemical reaction mechanisms. Although the eigenenergies of the nuclear Hamiltonian uniquely link a PES to its spectrum, this information is in general experimentally inaccess...

[Phys. Rev. A 97, 053410] Published Fri May 18, 2018

]]>Coherent perfect absorption (CPA) is investigated in the quantum nonlinear regime of cavity quantum electrodynamics (CQED), in which a single two-level atom couples to a single-mode cavity weakly driven by two identical laser fields. In the strong-coupling regime and due to the photon blockade effec...

[Phys. Rev. A 97, 053825] Published Fri May 18, 2018

]]>We propose an accessible scheme for implementing tunable nonlinear optical amplification and attenuation via a synergetic mechanism of four-wave mixing (FWM) and optical interference in a four-level ladder-type atomic system. By constructing a cyclic atom-field interaction, we show that two reverse ...

[Phys. Rev. A 97, 053826] Published Fri May 18, 2018

]]>We study the power of dephasing-covariant operations in the resource theories of coherence and entanglement. These are quantum operations whose actions commute with a projective measurement. In the resource theory of coherence, we find that any two states are asymptotically interconvertible under de...

[Phys. Rev. A 97, 050301(R)] Published Thu May 17, 2018

]]>We analyze the nonlinear propagation of a one-dimensional Airy beam. Under nonlinear focusing conditions, the Airy beam splits into a weak accelerating structure and a beam that has been named an “off-shooting soliton.” Experimental measurements and numerical results related to the off-shooting Airy...

[Phys. Rev. A 97, 051801(R)] Published Thu May 17, 2018

]]>We consider superconducting circuits for the purpose of simulating the spin-boson model. The spin-boson model consists of a single two-level system coupled to bosonic modes. In most cases, the model is considered in a limit where the bosonic modes are sufficiently dense to form a continuous spectral...

[Phys. Rev. A 97, 052321] Published Thu May 17, 2018

]]>The non-Born-Oppenheimer quantum dynamics of $pp\mu $ and $pd\mu $ molecular ions excited by ultrashort, superintense VUV laser pulses polarized along the molecular axis ($z$) is studied by the numerical solution of the time-dependent Schrödinger equation within a three-dimensional (3D) model, including the int...

[Phys. Rev. A 97, 053408] Published Thu May 17, 2018

]]>The existence and dynamics of solitons in quasi-one-dimensional Bose-Einstein condensates with spin-orbit coupling (SOC) and attractive two-body interactions are described for two coupled atomic pseudospin components with slowly and rapidly varying time-dependent Raman frequency. By varying the Rama...

[Phys. Rev. A 97, 053611] Published Thu May 17, 2018

]]>We examine the breathing mode of a strongly interacting two-dimensional Fermi gas and the role of temperature on the anomalous breaking of scale invariance. By calculating the equation of state with different many-body $T$-matrix theories and the virial expansion, we obtain a hydrodynamic equation of ...

[Phys. Rev. A 97, 053612] Published Thu May 17, 2018

]]>The algebraic quantification of nonclassicality, which naturally arises from the quantum superposition principle, is related to properties of regular nonclassicality quasiprobabilities. The latter are obtained by non-Gaussian filtering of the Glauber-Sudarshan $P$ function. They yield lower bounds for...

[Phys. Rev. A 97, 053823] Published Thu May 17, 2018

]]>A nonrelativistic Hamiltonian describing interaction between a mechanical degree of freedom and radiation pressure is commonly used as an ultimate tool for studying system behavior in optomechanics. This Hamiltonian is derived from the equation of motion of a mechanical degree of freedom and the opt...

[Phys. Rev. A 97, 053824] Published Thu May 17, 2018

]]>We unveil the geometrical meaning of winding number and utilize it to characterize the topological phases in one-dimensional chiral non-Hermitian systems. While chiral symmetry ensures the winding number of Hermitian systems are integers, it can take half integers for non-Hermitian systems. We give ...

[Phys. Rev. A 97, 052115] Published Wed May 16, 2018

]]>We use network analysis to describe and characterize an archetypal quantum system—an Ising spin chain in a transverse magnetic field. We analyze weighted networks for this quantum system, with link weights given by various measures of spin-spin correlations such as the von Neumann and Rényi mutual i...

[Phys. Rev. A 97, 052320] Published Wed May 16, 2018

]]>Resonant interatomic Coulombic decay (RICD) has been studied with HeNe dimers, where two decay channels are identified by bound HeNe${}^{+}$ states and low-energetic He+Ne${}^{+}$ fragments, and the state-resolved angular emission distributions of respective RICD electrons are examined in detail.

[Phys. Rev. A 97, 053407] Published Wed May 16, 2018

]]>Interactions in quantum systems may induce transitions to exotic correlated phases of matter which can be vulnerable to coupling to an environment. Here, we study the stability of a Bose-Hubbard chain coupled to a bosonic bath at zero and nonzero temperature. We show that only above a critical inter...

[Phys. Rev. A 97, 053610] Published Wed May 16, 2018

]]>We perform a Schrieffer-Wolff transformation to the two-photon Dicke model by keeping the leading-order correction with a quartic term of the field, which is crucial for finite-size scaling analysis. Besides a spectral collapse as a consequence of two-photon interaction, the super-radiant phase tran...

[Phys. Rev. A 97, 053821] Published Wed May 16, 2018

]]>Frequency combs are valuable metrological tools that have found several applications in spectroscopy and telecommunications. This work elucidates the physics behind their formation in diode lasers, which may spur further activities on the generation of frequency combs from chip-scale lasers.

[Phys. Rev. A 97, 053822] Published Wed May 16, 2018

]]>We address the emergence of entropy production in the nonequilibrium process of an open quantum system from the viewpoint of the environment. By making use of a dilation-based approach akin to the Stinespring theorem, we derive an expression for the entropy production that comprises two fundamental ...

[Phys. Rev. A 97, 050101(R)] Published Tue May 15, 2018

]]>We analyze the physics of optimal protocols to prepare a target state with high fidelity in a symmetrically coupled two-qubit system. By varying the protocol duration, we find a discontinuous phase transition, which is characterized by a spontaneous breaking of a ${\mathbb{Z}}_{2}$ symmetry in the functional form o...

[Phys. Rev. A 97, 052114] Published Tue May 15, 2018

]]>Reciprocal pairs of quantum channels are defined as completely positive transformations which admit a rigid, distance-preserving, yet not completely positive transformation that allows one to reproduce the outcome of one from the corresponding outcome of the other. From a classical perspective these...

[Phys. Rev. A 97, 052318] Published Tue May 15, 2018

]]>We propose an efficient scheme for transferring quantum states and generating entangled states between two qubits of different nature. The hybrid system consists of a single nitrogen-vacancy (NV) center and a superconducting (SC) qubit, which couple to an optical cavity and a microwave resonator, re...

[Phys. Rev. A 97, 052319] Published Tue May 15, 2018

]]>Exchange and correlations play a particularly important role in positronium (Ps) collisions with atoms and molecules, since the static potential for Ps interaction with a neutral system is zero. Theoretical description of both effects is a very challenging task. In the present work we use the free-e...

[Phys. Rev. A 97, 052707] Published Tue May 15, 2018

]]>For many atomic and molecular targets positronium (Ps) scattering looks very similar to electron scattering if total scattering cross sections are plotted as functions of the projectile velocity. Recently this similarity was observed for the resonant scattering by the ${\mathrm{N}}_{2}$ molecule. For correct treatm...

[Phys. Rev. A 97, 052708] Published Tue May 15, 2018

]]>We analyze the doubly differential electron momentum distribution in above-threshold ionization of atomic hydrogen by a linearly polarized mid-infrared laser pulse. We reproduce side rings in the momentum distribution with forward-backward symmetry previously observed by Lemell *et al.* [Phys. Rev. A **...**

[Phys. Rev. A 97, 053406] Published Tue May 15, 2018

]]>We measure the coherent scattering of low-intensity, near-resonant light by a cloud of laser-cooled two-level rubidium atoms with a size comparable to the wavelength of light. We isolate a two-level atomic structure by applying a 300-G magnetic field. We measure both the temporal and the steady-stat...

[Phys. Rev. A 97, 053816] Published Tue May 15, 2018

]]>Collective responses of localized surface plasmon resonances, known as surface lattice resonances (SLRs) in metal nanoparticle arrays, can lead to high quality factors ($\sim 100$), large local-field enhancements, and strong light-matter interactions. SLRs have found many applications in linear optics, bu...

[Phys. Rev. A 97, 053817] Published Tue May 15, 2018

]]>The Helmholtz equation can be written as coupled equations for the amplitude and phase. By considering spatial phase distributions corresponding to reflectionless wave propagation in the plane and solving for the amplitude in terms of this phase, we designed two-dimensional graded-index media which ...

[Phys. Rev. A 97, 053818] Published Tue May 15, 2018

]]>A generic computational imaging setup is considered which assumes sequential illumination of a semitransparent object by an arbitrary set of structured coherent illumination patterns. For each incident illumination pattern, all transmitted light is collected by a photon-counting bucket (single-pixel...

[Phys. Rev. A 97, 053819] Published Tue May 15, 2018

]]>We study the emergence and the stability of temporally localized structures in the output of a semiconductor laser passively mode locked by a saturable absorber in the long-cavity regime. For large yet realistic values of the linewidth enhancement factor, we disclose the existence of secondary dynam...

[Phys. Rev. A 97, 053820] Published Tue May 15, 2018

]]>We show how an upper bound for the ability to discriminate any number $N$ of candidates for the Hamiltonian governing the evolution of an open quantum system may be calculated by numerically efficient means. Our method applies an effective master-equation analysis to evaluate the pairwise overlaps bet...

[Phys. Rev. A 97, 052113] Published Mon May 14, 2018

]]>Interconnecting optical photons with superconducting circuits is a challenging problem but essential for building long-range superconducting quantum networks. We propose a hybrid quantum interface between the microwave and optical domains where the propagation of a single-photon pulse along a nanowa...

[Phys. Rev. A 97, 052315] Published Mon May 14, 2018

]]>We show that quantum Reed-Solomon codes constructed from classical Reed-Solomon codes can approach the capacity on the quantum erasure channel of $d$-level systems for large dimension $d$. We study the performance of one-way quantum repeaters with these codes and obtain a significant improvement in key ...

[Phys. Rev. A 97, 052316] Published Mon May 14, 2018

]]>Non-Gaussian states and operations are crucial for various continuous-variable quantum information processing tasks. To quantitatively understand non-Gaussianity beyond states, we establish a resource theory for non-Gaussian operations. In our framework, we consider Gaussian operations as free opera...

[Phys. Rev. A 97, 052317] Published Mon May 14, 2018

]]>The magnetic dipole ($M1$) line strength between the fine-structure levels of the ground configurations in B-, F-, Al-, and Cl-like ions are calculated for the four elements argon, iron, molybdenum, and tungsten. Systematically enlarged multiconfiguration Dirac-Hartree-Fock (MCDHF) wave functions are ...

[Phys. Rev. A 97, 052506] Published Mon May 14, 2018

]]>We demonstrate an experimentally feasible method for generating the classical Kelvin-Helmholtz instability in a single-component atomic Bose-Einstein condensate. By progressively reducing a potential barrier between two counterflowing channels, we seed a line of quantized vortices, which precede to ...

[Phys. Rev. A 97, 053608] Published Mon May 14, 2018

]]>An experimental proposal for realizing spin-orbit (SO) coupling of pseudospin 1 in the ground manifold ${}^{1}\mathrm{\Sigma}(\upsilon =0)$ of (bosonic) bialkali polar molecules is presented. The three spin components are composed of the ground rotational state and two substates from the first excited rotational level. Using hy...

[Phys. Rev. A 97, 053609] Published Mon May 14, 2018

]]>We propose an experimental scheme to generate, in a heralded fashion, arbitrary quantum superpositions of two-mode optical states with a fixed total photon number $n$ based on weakly squeezed two-mode squeezed state resources (obtained via weak parametric down-conversion), linear optics, and photon de...

[Phys. Rev. A 97, 053814] Published Mon May 14, 2018

]]>Long-distance quantum optical communications usually require efficient wave-mixing processes to convert the wavelengths of single photons. Many quantum applications based on electromagnetically induced transparency (EIT) have been proposed and demonstrated at the single-photon level, such as quantum...

[Phys. Rev. A 97, 053815] Published Mon May 14, 2018

]]>[Phys. Rev. A 97, 059904] Published Mon May 14, 2018

]]>The existence of the Efimov effect is drastically affected by the dimensionality of the space in which the system is embedded. The effective spatial dimension containing an atomic cloud can be continuously modified by compressing it in one or two directions. In the present Rapid Communication we det...

[Phys. Rev. A 97, 050701(R)] Published Fri May 11, 2018

]]>We investigate the nonequilibrium quantum heat transfer in a quantum thermal transistor, constructed by a triangle-coupled spin-boson system in a three-terminal setup. By exploiting the nonequilibrium noninteracting blip approximation approach combined with full counting statistics, we obtain the st...

[Phys. Rev. A 97, 052112] Published Fri May 11, 2018

]]>The representation of discrete, compact wavelet transformations (WTs) as circuits of local unitary gates is discussed. We employ a similar formalism as used in the multiscale representation of quantum many-body wave functions using unitary circuits, further cementing the relation established in the ...

[Phys. Rev. A 97, 052314] Published Fri May 11, 2018

]]>The energy splittings for $J=1$, $F=3/2$, $|{m}_{F}|=3/2$ hyperfine levels of the ${}^{3}{\mathrm{\Delta}}_{1}$ electronic state of ${}^{180}\mathrm{Hf}{}^{19}\mathrm{F}^{+}$ ion are calculated as functions of the external variable electric and magnetic fields within two approaches. In the first one, the transition to the rotating frame is performed, whereas in the se...

[Phys. Rev. A 97, 052504] Published Fri May 11, 2018

]]>The $K\beta $ x-ray spectra of the elements from Ca to Ge have been systematically investigated using a high-resolution antiparallel double-crystal x-ray spectrometer. Each $K{\beta}_{1,3}$ natural linewidth has been corrected using the instrumental function of this type of x-ray spectrometer, and the spin doublet en...

[Phys. Rev. A 97, 052505] Published Fri May 11, 2018

]]>Experimental schemes are proposed to engineer different types of anyon Hubbard models with ultracold two-component Fermi gases in an optical lattice, which may allow for the probing of fractional statistics of quasiparticles in one-dimensional anyonic models.

[Phys. Rev. A 97, 053605] Published Fri May 11, 2018

]]>We map the infrared dynamics of a relativistic single-component ($N=1$) interacting scalar field theory to that of nonrelativistic complex scalar fields. The Gross-Pitaevskii (GP) equation, describing the real-time dynamics of single-component ultracold Bose gases, is obtained at first nontrivial orde...

[Phys. Rev. A 97, 053606] Published Fri May 11, 2018

]]>We study the temperature regimes of the one-dimensional interacting gas to determine when the matter wave (c-field) theory is, in fact, correct and usable. The judgment is made by investigating the level of discrepancy in many observables at once in comparison to the exact Yang-Yang theory. We also ...

[Phys. Rev. A 97, 053607] Published Fri May 11, 2018

]]>Directional amplifiers are crucial nonreciprocal devices in both classical and quantum information processing. Here we propose a scheme for realizing a directional amplifier between optical and microwave fields based on an optomechanical system with optical gain, where an active optical cavity and t...

[Phys. Rev. A 97, 053812] Published Fri May 11, 2018

]]>We propose a scheme of stabilizing the persistent-current Rabi oscillation based on the flux qubit-resonator-atom hybrid structure. The low-$Q$ $LC$ resonator weakly interacts with the flux qubit and maps the persistent-current Rabi oscillation of the flux qubit onto the intraresonator electric field. T...

[Phys. Rev. A 97, 053813] Published Fri May 11, 2018

]]>We introduce a weakening of the preparation independence postulate of Pusey *et al.* [Nat. Phys. **8**, 475 (2012)] that does not presuppose that the space of ontic states resulting from a product-state preparation can be represented by the Cartesian product of subsystem state spaces. On the basis of this...

[Phys. Rev. A 97, 052109] Published Thu May 10, 2018

]]>A generalized principle of noncontextuality applicable to noisy experimental data is discussed. An approach to obtaining noise-robust noncontextuality inequalities starting from arbitrary statistical proofs of the Kochen-Specker theorem is presented.

[Phys. Rev. A 97, 052110] Published Thu May 10, 2018

]]>A neutron optical experiment is presented to investigate the paths taken by neutrons in a three-beam interferometer. In various beam paths of the interferometer, the energy of the neutrons is partially shifted so that the faint traces are left along the beam path. By ascertaining an operational mean...

[Phys. Rev. A 97, 052111] Published Thu May 10, 2018

]]>The repetition code is an important primitive for the techniques of quantum error correction. Here we implement repetition codes of at most 15 qubits on the 16 qubit *ibmqx3* device. Each experiment is run for a single round of syndrome measurements, achieved using the standard quantum technique of us...

[Phys. Rev. A 97, 052313] Published Thu May 10, 2018

]]>Subrotational cooling of the ${\mathrm{AlH}}^{+}$ ion to the miliKelvin regime, using optimally shaped pulses, is computed. The coherent electromagnetic fields induce purity-conserved transformations and do not change the sample temperature. A decrease in a sample temperature, manifested by an increase of purity, i...

[Phys. Rev. A 97, 053405] Published Thu May 10, 2018

]]>We consider many-body quantum systems dissipatively coupled by a cascade network, i.e., a setup in which interactions are mediated by unidirectional environmental modes propagating through a linear optical interferometer. In particular we are interested in the possibility of inducing different effec...

[Phys. Rev. A 97, 053811] Published Thu May 10, 2018

]]>[Phys. Rev. A 97, 059903] Published Thu May 10, 2018

]]>We propose a pulsed dynamical decoupling protocol as the generator of tunable, fast, and robust quantum phase gates between two microwave-driven trapped-ion hyperfine qubits. The protocol consists of sequences of $\pi $ pulses acting on ions that are oriented along an externally applied magnetic-field gr...

[Phys. Rev. A 97, 052312] Published Wed May 09, 2018

]]>The natural occupation numbers of fermionic systems are subject to nontrivial constraints, which include and extend the original *Pauli principle*. A recent mathematical breakthrough has clarified their mathematical structure and has opened up the possibility of a systematic analysis. Early investigat...

[Phys. Rev. A 97, 052503] Published Wed May 09, 2018

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