Different regimes of collective light scattering are observed when an elongated Bose-Einstein condensate is pumped by two noninterfering beams counterpropagating along its long axis. In the limit of small Rayleigh scattering rates, the presence of a second pump beam suppresses superradiance, whereas...

[Phys. Rev. A 96, 051603(R)] Published Wed Nov 22, 2017

]]>Simulating high-weight Hamiltonians can convert local noise on the original Hamiltonian into undesirable nonlocal noise on the simulated Hamiltonian. Here we show how, starting from a two-local Hamiltonian in the presence of non-Markovian noise, a desired computation can be simulated as well as prot...

[Phys. Rev. A 96, 052328] Published Wed Nov 22, 2017

]]>We propose a hybrid quantum repeater based on ancillary coherent field states and material qubits coupled to optical cavities. For this purpose, resonant qubit-field interactions and postselective field measurements are determined which are capable of realizing all necessary two-qubit operations for...

[Phys. Rev. A 96, 052329] Published Wed Nov 22, 2017

]]>We present a systematic study of the phenomena of number squeezing and fragmentation for a repulsive Bose-Einstein condensate (BEC) in a three-dimensional double-well potential over a range of interaction strengths and barrier heights, including geometries that exhibit appreciable overlap in the one...

[Phys. Rev. A 96, 053627] Published Wed Nov 22, 2017

]]>High-dimensional entangled photon pairs have many excellent properties compared to two-dimensional entangled two-photon states, such as greater information capacity, stronger nonlocality, and higher security. Traditionally, the degree of freedom that can produce high-dimensional entanglement mainly ...

[Phys. Rev. A 96, 053849] Published Wed Nov 22, 2017

]]>The microwave clock frequency of the $|5s{\phantom{\rule{0.16em}{0ex}}}^{2}{S}_{1/2},F=0,{m}_{F}=0\rangle \leftrightarrow |5s{\phantom{\rule{0.16em}{0ex}}}^{2}{S}_{1/2},F=1,{m}_{F}=0\rangle $ transition in the ${}^{113}\mathrm{Cd}^{+}$ ion has been reported as 15 199 862 855.0192(10) Hz [Opt. Lett. **40**, 4249 (2015)]. Fractional systematic shift $\left(\beta \right)$ due to the black-body radiation (BBR) arising from the Stark effect in the above, the ...

[Phys. Rev. A 96, 050502(R)] Published Tue Nov 21, 2017

]]>We derive general conditions for the compatibility of channels in general probabilistic theory. We introduce formalism that allows us to easily formulate steering by channels and Bell nonlocality of channels as generalizations of the well-known concepts of steering by measurements and Bell nonlocali...

[Phys. Rev. A 96, 052127] Published Tue Nov 21, 2017

]]>We report an experimental determination of the ground-state hyperfine constant $A$ of the ${}^{25}\mathrm{Mg}^{+}$ ions by measuring the $|{S}_{1/2},F=2,m=0\rangle $ to $|{S}_{1/2},F=3,m=0\rangle $ transition (0-0 transition) frequency of the two ground-state hyperfine energy levels. The frequency is measured by rf resonant method in a Paul trap u...

[Phys. Rev. A 96, 052507] Published Tue Nov 21, 2017

]]>We report fully differential photoelectron spectra from an *ab initio* coupled-channels treatment of ${\mathrm{CO}}_{2}$. Photoionization by laser pulses centered at wavelengths of 400 and 800 nm is considered, with arbitrary molecular alignment and polarization (linear and elliptic). Calculations reveal significant ...

[Phys. Rev. A 96, 053421] Published Tue Nov 21, 2017

]]>We study the ground-state phase diagram of two-dimensional two-component (or pseudospin-$\frac{1}{2}$) Bose gases in a high synthetic magnetic field in the space of the total filling factor and the ratio of the intercomponent coupling ${g}_{\uparrow \downarrow}$ to the intracomponent one $g>0$. Using exact diagonalization, we find t...

[Phys. Rev. A 96, 053626] Published Tue Nov 21, 2017

]]>We consider the Riemann problem of evolution of initial discontinuities for the photon fluid propagating in a normal dispersion fiber with account of self-steepening effects. The dynamics of light field is described by the nonlinear Schrödinger (NLS) equation with self-steepening term appearing due ...

[Phys. Rev. A 96, 053844] Published Tue Nov 21, 2017

]]>We show that anti-$\mathcal{PT}$ symmetry can be realized in dissipatively coupled optical systems. Its emergence gives rise to spontaneous phase transitions for the guided and localized photonic eigenmodes in the waveguide and cavity systems studied, respectively. As a ubiquitous feature we demonstrate that co...

[Phys. Rev. A 96, 053845] Published Tue Nov 21, 2017

]]>Circular polarization-entangled photons can be used to obtain an enhancement of the precision in a rotation measurement. In this paper, the method of entanglement transformation is used to produce NOON states in circular polarization from a readily generated linear polarization-entangled photon sour...

[Phys. Rev. A 96, 053846] Published Tue Nov 21, 2017

]]>We put forward a generic method that enables lossless generation of pure single photons with arbitrary shape over any degree of freedom or several degrees of freedom simultaneously. The method exploits pairs of entangled photons. One of the photons is the subject for lossy shaping manipulations foll...

[Phys. Rev. A 96, 053847] Published Tue Nov 21, 2017

]]>We study numerically the spatial dynamics of light in periodic square lattices in the presence of a Kerr term, emphasizing the peculiarities stemming from the nonlinearity. We find that, under rather general circumstances, the phase pattern of the stable ground state depends on the character of the ...

[Phys. Rev. A 96, 053848] Published Tue Nov 21, 2017

]]>Attosecond photoelectron spectroscopy allows the observation of electronic processes on attosecond time scales ($1\phantom{\rule{0.28em}{0ex}}\text{as}\phantom{\rule{0.28em}{0ex}}=\phantom{\rule{0.28em}{0ex}}{10}^{-18}$ s), as has been demonstrated in proof-of-principle experiments that probe the electronic dynamics in isolated atoms with unprecedented accuracy. Its recent expansion to solid tar...

[Phys. Rev. A 96, 051403(R)] Published Mon Nov 20, 2017

]]>We analyze the time evolution of two kinds of coherent states for a particle in a Pöschl-Teller potential. We find a pair of canonically conjugate operators and compare the behavior of their time evolution for both coherent states. The nonlinear ones are more localized. The trajectory in the phase s...

[Phys. Rev. A 96, 052122] Published Mon Nov 20, 2017

]]>Quantum mechanics presents peculiar properties that, on the one hand, have been the subject of several theoretical and experimental studies about its very foundations and, on the other hand, provide tools for developing new technologies, the so-called quantum technologies. The nonclassicality pointe...

[Phys. Rev. A 96, 052123] Published Mon Nov 20, 2017

]]>We study the breaking of the discrete time-translation symmetry in small periodically driven quantum systems. These systems are intermediate between large closed systems and small dissipative systems, which both display such symmetry breaking but have qualitatively different dynamics. As a nontrivia...

[Phys. Rev. A 96, 052124] Published Mon Nov 20, 2017

]]>An exact reduced dynamical map along with its operator sum representation is derived for a central spin interacting with a thermal spin environment. The dynamics of the central spin shows high sustainability of quantum traits such as coherence and entanglement in the low-temperature regime. However,...

[Phys. Rev. A 96, 052125] Published Mon Nov 20, 2017

]]>Born's rule, which postulates the probability of a measurement outcome in a quantum state, is pivotal to interpretations and applications of quantum mechanics. By exploiting the departure of the product of two Hermitian operators in Born's rule from Hermiticity, we prescribe an intrinsic and natural...

[Phys. Rev. A 96, 052126] Published Mon Nov 20, 2017

]]>We investigate the validity of two common assumptions in the modeling of superconducting circuits: first, that the superconducting qubits are pointlike and, second, that the UV behavior of the transmission line is not relevant to the qubit dynamics. We show that in the experimentally accessible ultr...

[Phys. Rev. A 96, 052325] Published Mon Nov 20, 2017

]]>We consider the uncertainty bound on the sum of variances of two incompatible observables in order to derive a corresponding steering inequality. Our steering criterion, when applied to discrete variables, yields the optimum steering range for two-qubit Werner states in the two-measurement and two-o...

[Phys. Rev. A 96, 052326] Published Mon Nov 20, 2017

]]>The problem studied in this paper is, if the number of queries to unitary operations is fixed, say $k$, then when do local operations and classical communication (LOCC) suffice for optimally distinguishing bipartite unitary operations? We consider the above problem for two-qubit unitary operations in ...

[Phys. Rev. A 96, 052327] Published Mon Nov 20, 2017

]]>Angle-differential elastic electron-scattering cross section, $\frac{d\sigma}{d\mathrm{\Omega}}$, for a 20-eV electron collision with a half-filled-subshell $\mathrm{Mn}(...3{d}^{5}\phantom{\rule{0.16em}{0ex}}4{s}^{2},{}^{6}S)$ atom is studied using a semiempirical static polarization potential of the atom in the calculations. The study is in order, primarily due to noticeable disc...

[Phys. Rev. A 96, 052704] Published Mon Nov 20, 2017

]]>The nonmonotonic energy dependence of the $\mathrm{L}{\mathrm{i}}^{0}$ fraction on high-work-function surfaces has not been understood so far. To further study this phenomenon, in this work, efficient neutralization of $\mathrm{N}{\mathrm{a}}^{+}$ ions has been reported on various surfaces, instead of $\mathrm{L}{\mathrm{i}}^{+}$ ions. The nonmonotonic energy dependence of...

[Phys. Rev. A 96, 052705] Published Mon Nov 20, 2017

]]>High-harmonic generation by a laser-driven solid slab is simulated using time-dependent density functional theory. Multiple harmonic plateaus up to very high harmonic orders are observed already at surprisingly low field strengths. The full all-electron harmonic spectra are, in general, very differe...

[Phys. Rev. A 96, 053418] Published Mon Nov 20, 2017

]]>We introduce the optimal fingerprinting process which is aimed at accurately identifying the parameters which characterize the dynamics of a physical system. A database is first built from the time evolution of an ensemble of dynamical systems driven by a specific field, which is designed by optimal...

[Phys. Rev. A 96, 053419] Published Mon Nov 20, 2017

]]>An attosecond XUV or x-ray pump-control scheme for the electron-spectral-line profiles of Fano and Auger resonances is proposed and studied. A weak pump resonantly excites the atom and creates the resonance, and then a second strong attosecond control pulse resonantly coupling the resonance to an va...

[Phys. Rev. A 96, 053420] Published Mon Nov 20, 2017

]]>We perform the experimental demonstration of the method proposed earlier [F. P. Dos Santos, Phys. Rev. A **91**, 063615 (2015)] to extract the differential phase in dual atom interferometers. From a single magneto-optical trap, we generate two atomic sources, vertically separated and free falling synchr...

[Phys. Rev. A 96, 053624] Published Mon Nov 20, 2017

]]>We theoretically investigate a two-dimensional harmonically trapped gas of identical atoms with Rashba spin-orbit coupling and no interatomic interactions. In analogy with the spin Hall effect in uniform space, the gas exhibits a spin Hall mode. In particular, in response to a displacement of the ce...

[Phys. Rev. A 96, 053625] Published Mon Nov 20, 2017

]]>An absolute optical instrument is a region of space, typically defined by a spatially varying index of refraction, in which bound ray trajectories are closed. Traditional examples of such devices include Maxwell's fisheye and the Eaton and Luneburg lenses. In this paper we employ the close analogy b...

[Phys. Rev. A 96, 053838] Published Mon Nov 20, 2017

]]>The energy absorption and energy extinction cross sections of an object in uniform translational motion in free space are Lorentz invariant, but the total energy scattering cross section is not. Indeed, the forward-scattering theorem holds true for comoving observers but not for other inertial obser...

[Phys. Rev. A 96, 053839] Published Mon Nov 20, 2017

]]>We demonstrate the importance of considering correlations between degenerate Zeeman sublevels that develop in dense atomic ensembles. In order to do this, we develop a set of equations capable of simulating large numbers of atoms while still incorporating correlations between degenerate Zeeman suble...

[Phys. Rev. A 96, 053840] Published Mon Nov 20, 2017

]]>We study Bragg-induced power oscillations in Fourier space between a pair of optical resonant transverse modes propagating through a periodic $\mathcal{PT}$-symmetric lattice, represented by a refractive index that includes gain and loss in a balanced way. Our results imply that the $\mathcal{PT}$-symmetric system shows ex...

[Phys. Rev. A 96, 053841] Published Mon Nov 20, 2017

]]>Optical quantum protocols are reliant on the production of highly pure single photons. However, most parametric heralded single-photon sources possess spectral correlations, limiting the purity of the produced photon. The most common method for restoring the purity is with narrowband spectral filter...

[Phys. Rev. A 96, 053842] Published Mon Nov 20, 2017

]]>We propose an ultrafast femtosecond time scale trichromatic $\pi $-pulse illumination scheme for coherent excitation and manipulation of low-lying Rydberg states in rubidium. Selective population of ${nP}_{3/2}$ levels with principal quantum numbers $n\lesssim 12$ using 75-fs laser pulses is achieved. The density-matrix ...

[Phys. Rev. A 96, 053843] Published Mon Nov 20, 2017

]]>Sensing, localizing, and identifying individual nuclear spins or frequency components of a signal in the presence of a noisy environment requires the development of robust and selective methods of dynamical decoupling. An important challenge that remains to be addressed in this context are spurious ...

[Phys. Rev. A 96, 051402(R)] Published Fri Nov 17, 2017

]]>We establish a connection between an arbitrary Hermitian tight-binding model with chiral ($\mathcal{C}$) symmetry and its non-Hermitian counterpart with chiral-time ($\mathcal{CT}$) symmetry. We show that such a non-Hermitian Hamiltonian is pseudo-Hermitian. The eigenvalues and eigenvectors of the non-Hermitian Hamiltonian...

[Phys. Rev. A 96, 052121] Published Fri Nov 17, 2017

]]>We present a comprehensive treatise on the derivation of the factorization formula describing strong-field photoelectron momentum distributions near the outermost backward rescattering caustic within the adiabatic theory and its validation by calculations. The formula derived holds for ionization by...

[Phys. Rev. A 96, 053416] Published Fri Nov 17, 2017

]]>We develop the research achievement of recent work [Gärttner *et al.*, Phys. Rev. Lett. **113**, 233002 (2014)], in which an anomalous excitation enhancement is observed in a three-level Rydberg-atom ensemble with many-body coherence. In our theoretical analysis, this effect is ascribed to the existence ...

[Phys. Rev. A 96, 053417] Published Fri Nov 17, 2017

]]>We introduce and investigate a system that uses temporal resonance-induced phase-space pathways to create strong coupling between an atomic Bose-Einstein condensate and a traveling optical lattice potential. We show that these pathways thread both the classical and quantum phase space of the atom cl...

[Phys. Rev. A 96, 053623] Published Fri Nov 17, 2017

]]>The fundamental active photonic dimer consisting of two coupled quantum well lasers is investigated in the context of the rate-equation model. Spectral transition properties and exceptional points are shown to occur under general conditions, not restricted by parity-time symmetry as in coupled-mode ...

[Phys. Rev. A 96, 053837] Published Fri Nov 17, 2017

]]>We investigate the generation of entanglement (spin squeezing) in an optical-transition atomic clock through the coupling to an optical cavity in its vacuum state. We show that if each atom is prepared in a superposition of the ground state and a long-lived electronic excited state, and viewed as a ...

[Phys. Rev. A 96, 050301(R)] Published Thu Nov 16, 2017

]]>We study a quantum Otto engine embedding a working substance composed of a two-level system interacting with a harmonic mode. The physical properties of the substance are described by a generalized quantum Rabi model arising in superconducting circuit realizations. We show that light-matter quantum ...

[Phys. Rev. A 96, 052119] Published Thu Nov 16, 2017

]]>Quantum entanglement and nonlocality are inequivalent notions: There exist entangled states that nevertheless admit local-realistic interpretations. This paper studies a special class of local-hidden-variable theories, in which the linear structure of quantum measurement operators is preserved. It h...

[Phys. Rev. A 96, 052120] Published Thu Nov 16, 2017

]]>Recently, there has been a renewed interest in the quantification of coherence or other coherencelike concepts within the framework of quantum resource theory. However, rigorously defined or not, the notion of *coherence* or *decoherence* has already been used by the community for decades since the adve...

[Phys. Rev. A 96, 052322] Published Thu Nov 16, 2017

]]>Experimental detection of entanglement of an arbitrary state of a given bipartite system is crucial for exploring many areas of quantum information processing. But such a detection should be made in a device-independent way if the preparation process of the state is considered to be faithful, in ord...

[Phys. Rev. A 96, 052323] Published Thu Nov 16, 2017

]]>We consider how to quantify non-Gaussianity for the correlation of a bipartite quantum state by using various measures such as relative entropy and geometric distances. We first show that an intuitive approach, i.e., subtracting the correlation of a reference Gaussian state from that of a target non...

[Phys. Rev. A 96, 052324] Published Thu Nov 16, 2017

]]>An atom interferometer using a Bose–Einstein condensate of ${}^{87}\mathrm{Rb}$ atoms is utilized for the measurement of magnetic-field gradients. Composite optical pulses are used to construct a spatially symmetric Mach–Zehnder geometry. By using a biased interferometer we demonstrate the ability to measure small ...

[Phys. Rev. A 96, 053622] Published Thu Nov 16, 2017

]]>[Phys. Rev. A 96, 059905] Published Thu Nov 16, 2017

]]>The energy eigenstates of a spin-$\frac{1}{2}$ particle in a magnetic field confined to a plane, define a planar spin. If the particle moves adiabatically around a loop in this plane, it picks up a topological Berry phase that can only be an integer multiple of $\pi $. We propose a neutron-interferometry test of th...

[Phys. Rev. A 96, 052117] Published Wed Nov 15, 2017

]]>In the lore of quantum metrology, one often hears (or reads) the following no-go theorem: If you put a vacuum into one input port of a balanced Mach-Zehnder interferometer, then no matter what you put into the other input port, and no matter what your detection scheme, the sensitivity can never be b...

[Phys. Rev. A 96, 052118] Published Wed Nov 15, 2017

]]>Single-shot qubit readout typically combines high readout contrast with long-lived readout signals, leading to large signal-to-noise ratios and high readout fidelities. In recent years, it has been demonstrated that both readout contrast and readout signal lifetime, and thus the signal-to-noise rati...

[Phys. Rev. A 96, 052321] Published Wed Nov 15, 2017

]]>The finite terms Hylleraas- and Kinoshita-type variational wave functions are considered for three-body systems. In the Coulombic case local properties of wave functions are restricted by the Kato's cusp conditions. It is showed that Kato's cusp conditions restrict the possible terms in variational ...

[Phys. Rev. A 96, 052506] Published Wed Nov 15, 2017

]]>Time-resolved ultrafast x-ray scattering from photoexcited matter is an emerging method to image ultrafast dynamics in matter with atomic-scale spatial and temporal resolutions. For a correct and rigorous understanding of current and upcoming imaging experiments, we present the theory of time-resolv...

[Phys. Rev. A 96, 053413] Published Wed Nov 15, 2017

]]>We measured angle-resolved high-energy electron spectra emitted from ${\mathrm{C}}_{2}{\mathrm{H}}_{4}$ in an intense laser field, extracted field-free electron-ion elastic scattering differential cross sections (DCSs) according to quantitative rescattering theory, and obtained molecular contrast factors (MCFs) subtracting the i...

[Phys. Rev. A 96, 053414] Published Wed Nov 15, 2017

]]>We report on the realization of a transversely loaded two-dimensional magneto-optical trap serving as a source for cold strontium atoms. We analyze the dependence of the source's properties on various parameters, in particular the intensity of a pushing beam accelerating the atoms out of the source....

[Phys. Rev. A 96, 053415] Published Wed Nov 15, 2017

]]>We present a universal theory for the critical behavior of an impurity at the two-dimensional superfluid–Mott-insulator transition. Our analysis is motivated by a numerical study of the Bose-Hubbard model with an impurity site by Huang *et al.* [Phys. Rev. B **94**, 220502 (2016)]; they found an impurity ...

[Phys. Rev. A 96, 053620] Published Wed Nov 15, 2017

]]>One of the challenges for fermionic cold-atom experiments in optical lattices is to cool the systems to low enough temperature so that they can form quantum degenerate ordered phases. In particular, there has been significant work in trying to find the antiferromagnetic phase transition of the Hubba...

[Phys. Rev. A 96, 053621] Published Wed Nov 15, 2017

]]>We study theoretically stimulated Brillouin scattering (SBS) in silicon nitride (SiN) waveguides created as a phononic line defect inside a pillar-based phononic-crystal membrane of the same material for efficient confinement of the generated acoustic phonons to the optical waveguides. The phononic ...

[Phys. Rev. A 96, 053836] Published Wed Nov 15, 2017

]]>We propose an extension of quantum mechanics based on the idea that the underlying “quantum noise” has a nonzero, albeit very small, correlation time ${\tau}_{c}$. The standard (nonrelativistic) Schrödinger equation is recovered to zeroth order in ${\tau}_{c}$, and the first correction to energy levels is computed. Som...

[Phys. Rev. A 96, 052116] Published Tue Nov 14, 2017

]]>Quantum coherence has recently emerged as a key candidate for use as a resource in various quantum information processing tasks. Therefore, it is of utmost importance to explore the possibility of creating a greater number of coherent states from an existing coherent pair. In other words, we start w...

[Phys. Rev. A 96, 052319] Published Tue Nov 14, 2017

]]>We present a blueprint for building a fault-tolerant universal quantum computer with Rydberg atoms. Our scheme, which is based on the surface code, uses individually addressable, optically trapped atoms as qubits and exploits electromagnetically induced transparency to perform the multiqubit gates r...

[Phys. Rev. A 96, 052320] Published Tue Nov 14, 2017

]]>We use a magnetometer probe based on the Zeeman shift of the rubidium resonant optical transition to explore the atomic magnetic response for a wide range of field values. We record optical spectra for fields from a few tesla up to 60 T, the limit of the coil producing the magnetic field. The atomic...

[Phys. Rev. A 96, 052504] Published Tue Nov 14, 2017

]]>We report a detailed molecular spectroscopy study of the lowest excited electronic states of ${}^{23}\mathrm{Na}\phantom{\rule{0.16em}{0ex}}{}^{87}\mathrm{Rb}$ for producing ultracold ${}^{23}\mathrm{Na}\phantom{\rule{0.16em}{0ex}}{}^{87}\mathrm{Rb}$ molecules in the electronic, rovibrational, and hyperfine ground state. Starting from weakly bound Feshbach molecules, a series of vibrational levels of the $A{\phantom{\rule{0.16em}{0ex}}}^{1}{\mathrm{\Sigma}}^{+}\text{\u2212}b{\phantom{\rule{0.16em}{0ex}}}^{3}\mathrm{\Pi}$...

[Phys. Rev. A 96, 052505] Published Tue Nov 14, 2017

]]>The quantum theory of coherent Ising machines, based on degenerate optical parametric oscillators and measurement-feedback circuits, is developed using the positive $P(\alpha ,\beta )$ representation of the density operator and the master equation. The theory is composed of the c-number stochastic differential e...

[Phys. Rev. A 96, 053833] Published Tue Nov 14, 2017

]]>Recently, the coherent Ising machine (CIM) as a degenerate optical parametric oscillator (DOPO) network has been researched to solve Ising combinatorial optimization problems. We formulate a theoretical model for the CIM with discrete-time measurement feedback processes, and perform numerical simula...

[Phys. Rev. A 96, 053834] Published Tue Nov 14, 2017

]]>The addition or subtraction of a photon from a Gaussian state of light is a versatile and experimentally feasible procedure to create non-Gaussian states. In multimode setups, these states manifest a wide range of phenomena when the photon is added or subtracted in a mode-tunable way. In this paper ...

[Phys. Rev. A 96, 053835] Published Tue Nov 14, 2017

]]>van der Waals interactions govern the physics of a plethora of molecular structures. It is well known that the leading term in the distance-based London expansion of the van der Waals energy for atomic and molecular dimers decays as $1/{R}^{6}$, where $R$ is the dimer distance. Using perturbation theory, we ...

[Phys. Rev. A 96, 050501(R)] Published Mon Nov 13, 2017

]]>The super Efimov effect is a recently proposed three-body effect characterized by a double-exponential scaling, which has not yet been observed experimentally. Here, we present the general dynamic equations determining the cloud size of a scale-invariant quantum gas in a time-dependent harmonic trap...

[Phys. Rev. A 96, 050702(R)] Published Mon Nov 13, 2017

]]>We develop a class of supercell photonic crystals supporting complete photonic band gaps based on breaking spatial symmetries of the underlying primitive photonic crystal. One member of this class based on a two-dimensional honeycomb structure supports a complete band gap for an index-contrast ratio...

[Phys. Rev. A 96, 051802(R)] Published Mon Nov 13, 2017

]]>Several recent results on thermodynamics have been obtained using the tools of quantum information theory and resource theories. So far, the resource theories utilized to describe thermodynamics have assumed the existence of an infinite thermal reservoir, by declaring that thermal states at some bac...

[Phys. Rev. A 96, 052112] Published Mon Nov 13, 2017

]]>It is by now well established that noise itself can be useful for performing quantum information processing tasks. We present results which show how one can effectively reduce the error rate associated with a noisy quantum channel by counteracting its detrimental effects with another form of noise. ...

[Phys. Rev. A 96, 052113] Published Mon Nov 13, 2017

]]>There has been an increasing interest in the quantification of nearly deterministic work extraction from a finite number of copies of microscopic particles in finite time. This paradigm, the so-called single-shot $\epsilon $-deterministic work extraction, considers processes with small failure probabilities. ...

[Phys. Rev. A 96, 052114] Published Mon Nov 13, 2017

]]>For a quantum system undergoing a unitary, process work is commonly defined based on the two projective measurement protocols, which measures the energies of the system before and after the process. However, it is well known that projective measurements disregard quantum coherences of the system wit...

[Phys. Rev. A 96, 052115] Published Mon Nov 13, 2017

]]>Memory-assisted measurement-device-independent quantum key distribution (MA-MDI-QKD) is a promising scheme that aims to improve the rate-versus-distance behavior of a QKD system by using the state-of-the-art devices. It can be seen as a bridge between current QKD links to quantum repeater based netw...

[Phys. Rev. A 96, 052313] Published Mon Nov 13, 2017

]]>It is a computationally hard task to certify genuine multipartite entanglement (GME). We investigate the relation between the norms of the correlation vectors and the detection of GME for tripartite quantum systems. A sufficient condition for GME and an effective lower bound for the GME concurrence ...

[Phys. Rev. A 96, 052314] Published Mon Nov 13, 2017

]]>One way to study the physical plausibility of closed timelike curves (CTCs) is to examine their computational power. This has been done for Deutschian CTCs (D-CTCs) and postselection CTCs (P-CTCs), with the result that they allow for the efficient solution of problems in PSPACE and PP, respectively....

[Phys. Rev. A 96, 052315] Published Mon Nov 13, 2017

]]>Nonadiabatic geometric quantum computation provides a means to perform fast and robust quantum gates. It has been implemented in various physical systems, such as trapped ions, nuclear magnetic resonance, and superconducting circuits. Another system being adequate for implementation of nonadiabatic ...

[Phys. Rev. A 96, 052316] Published Mon Nov 13, 2017

]]>Cat-state qubits (qubits encoded with cat states) have recently drawn intensive attention due to their enhanced lifetimes with quantum error correction. We here propose a method to implement a universal controlled-phase gate of two cat-state qubits via two microwave resonators coupled to a supercond...

[Phys. Rev. A 96, 052317] Published Mon Nov 13, 2017

]]>It is known that no quantum process can produce a predetermined superposition of unknown arbitrary states. It has already been shown that with some partial information about the states, one can produce with some probability such superpositions. In general the success probability of these machines, e...

[Phys. Rev. A 96, 052318] Published Mon Nov 13, 2017

]]>The electron-capture processes in ${\mathrm{C}}^{4+}$ + He collisions have been studied theoretically using a two-active-electron semiclassical atomic-orbital close-coupling method in a wide energy domain. The results of the present calculations are compared with available theoretical predictions and experimental m...

[Phys. Rev. A 96, 052703] Published Mon Nov 13, 2017

]]>Strong dipole-exchange interactions due to spontaneously produced contaminant states can trigger rapid dephasing in many-body Rydberg ensembles [E. A. Goldschmidt *et al.*, Phys. Rev. Lett. **116**, 113001 (2016)]. Such broadening has serious implications for many proposals to coherently use Rydberg inte...

[Phys. Rev. A 96, 053409] Published Mon Nov 13, 2017

]]>We present estimates of the attosecond streaking delay in photoionization of atoms based on an analytical formula. In the derivation of the formula we use that the streaking delay depends on the propagation of the photoelectron over a finite range in space. We find that the analytical estimates agre...

[Phys. Rev. A 96, 053410] Published Mon Nov 13, 2017

]]>The accurate determination of atomic final states following nuclear $\beta $ decay plays an important role in several experiments. In particular, the charge state distributions of ions following nuclear $\beta $ decay are important for determinations of the $\beta \text{\u2212}\nu $ angular correlation with improved precision. Beyond ...

[Phys. Rev. A 96, 053411] Published Mon Nov 13, 2017

]]>A two-step photoionization strategy of an ultracold rubidium beam for application in a focused ion beam instrument is analyzed and implemented. In this strategy the atomic beam is partly selected with an aperture after which the transmitted atoms are ionized in the overlap of a tightly cylindrically...

[Phys. Rev. A 96, 053412] Published Mon Nov 13, 2017

]]>Stabilizing vortex solitons with high values of the topological charge $S$ is a challenging issue in optics, studies of Bose-Einstein condensates (BECs), and other fields. To develop an approach to the solution of this problem, we consider a two-dimensional dipolar BEC under the action of an axisymmet...

[Phys. Rev. A 96, 053617] Published Mon Nov 13, 2017

]]>We numerically study a rotating Bose-Einstein condensate placed transiently over the critical rotation frequency, i.e., in a regime where the rotation frequency is larger than the radial frequency of the confinement. We study the reversibility of this process depending on the strength of the interac...

[Phys. Rev. A 96, 053618] Published Mon Nov 13, 2017

]]>Synthetic spin-orbit coupling in ultracold atomic gases can be taken to extremes rarely found in solids. We study a two-dimensional Hubbard model of bosons in an optical lattice in the presence of spin-orbit coupling strong enough to drive direct transitions from Mott insulators to superfluids. Here...

[Phys. Rev. A 96, 053619] Published Mon Nov 13, 2017

]]>We propose a scheme to achieve a strong photon antibunching with a degenerate optical parametric amplifier coupled to a cavity via unconventional photon blockade. The photon blockade occurs as a result of the suppression of two-photon excitation due to a quantum interference effect between different...

[Phys. Rev. A 96, 053827] Published Mon Nov 13, 2017

]]>In an optically absorbing or amplifying linear medium, the energy flow density of interfering optical waves is in general periodically modulated in space. This makes the wave transmission through a material boundary, as described by the Fresnel transmission coefficients, nonreciprocal and apparently...

[Phys. Rev. A 96, 053828] Published Mon Nov 13, 2017

]]>Two-dimensional (2D) spectroscopy has been intensively used to study electronic and vibronic coherences in biological systems and semiconductors. This technique studies coherent as well as incoherent signals that arise from the nonlinear interaction of a sequence of laser pulses. In this paper we pr...

[Phys. Rev. A 96, 053830] Published Mon Nov 13, 2017

]]>We study the output entanglement in a three-mode optomechanical system via reservoir engineering by shifting the center frequency of filter function away from resonant frequency. We find the bandwidth of the filter function can suppress the entanglement in the vicinity of resonant frequency of the s...

[Phys. Rev. A 96, 053831] Published Mon Nov 13, 2017

]]>We present an approach to achieve efficient single-photon frequency conversion in the microwave domain based on coherent control in superconducting quantum circuits, which consist of a driven artificial atom coupled to a semi-infinite transmission line. Using the full quantum-mechanical method, we a...

[Phys. Rev. A 96, 053832] Published Mon Nov 13, 2017

]]>[Phys. Rev. A 96, 059904] Published Mon Nov 13, 2017

]]>Ultracold Fermi atoms confined in optical lattices coupled to quantized modes of an optical cavity are an ideal scenario to engineer quantum simulators in the strongly interacting regime. The system has both short-range and cavity-induced long-range interactions. We propose such a scheme to investig...

[Phys. Rev. A 96, 051602(R)] Published Fri Nov 10, 2017

]]>We consider a type of light-dressing effect in molecules which is due to laser-induced deformation of molecules. We derive general formulas which describe the change of the equilibrium bond lengths, bending angles, and vibration frequencies for a polyatomic molecule. Up to the second-order terms in ...

[Phys. Rev. A 96, 053408] Published Fri Nov 10, 2017

]]>Photoassociation of ultracold atoms with pulsed laser light is shown to lead to alignment of the product molecules along the excitation laser polarization axis. We theoretically investigate pulsed two-photon photoassociation of ${}^{87}\mathrm{Rb}$ atoms into a specific weakly bound level of the $a{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{\Sigma}}_{u}^{+}$ metastable el...

[Phys. Rev. A 96, 053613] Published Fri Nov 10, 2017

]]>We consider a three-component Fermi gas that has SU(3) symmetry and is confined to two dimensions (2D). For realistic cold atomic gas experiments, we show that the phase diagram of the quasi-2D system can be characterized using two 2D scattering parameters: the scattering length and the effective ra...

[Phys. Rev. A 96, 053614] Published Fri Nov 10, 2017

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