Magnetic-field strengths are measured with high precision. The results indicate the possibility of using Rydberg atoms for sensing strong magnetic fields.

[Phys. Rev. A 95, 061804(R)] Published Tue Jun 27, 2017

]]>A nonadiabatic and robust method of excitation transfer in a non-Hermitian tight-binding linear chain, assisted by an imaginary gauge field, is theoretically proposed. The gauge field undergoes a linear gradient in time, from a negative to a positive value, which results in an effective transfer of ...

[Phys. Rev. A 95, 062122] Published Tue Jun 27, 2017

]]>We present a protocol for interleaved randomized benchmarking of arbitrary quantum gates using Monte Carlo sampling of quantum states. It is generally applicable, including non-Clifford gates while preserving key advantages of randomized benchmarking such as error amplification as well as independen...

[Phys. Rev. A 95, 062335] Published Tue Jun 27, 2017

]]>Conventional methods for computing maximum-likelihood estimators (MLE) often converge slowly in practical situations, leading to a search for simplifying methods that rely on additional assumptions for their validity. In this work, we provide a fast and reliable algorithm for maximum-likelihood reco...

[Phys. Rev. A 95, 062336] Published Tue Jun 27, 2017

]]>We critically examine the current status of theoretical calculations of the energies, the fine structure, and the isotope shift of the lowest-lying states of helium, searching for unresolved discrepancies with experiments. Calculations are performed within the quantum electrodynamics expansion in po...

[Phys. Rev. A 95, 062510] Published Tue Jun 27, 2017

]]>We investigate electron-correlation effects in the $g$ factor of the ground state of Li-like ions. Our calculations are performed within the nonrelativistic quantum electrodynamics (NRQED) expansion up to two leading orders in the fine-structure constant $\alpha ,{\alpha}^{2}$, and ${\alpha}^{3}$. The dependence of the NRQED resu...

[Phys. Rev. A 95, 062511] Published Tue Jun 27, 2017

]]>A charged particle in a magnetic field possesses discrete energy levels associated with particle rotation around the field lines. The radiative transitions between these levels are the well-known cyclotron transitions. We show that a bound complex of particles with a nonzero net charge displays anal...

[Phys. Rev. A 95, 062512] Published Tue Jun 27, 2017

]]>We extended the multiconfiguration Hartree-Fock (MCHF) + effective charge (EFC) method for double photoionization of atoms and investigated the effect of valence-electron correlation in the double $K$-shell photoionization of atomic beryllium. We used the MCHF method, which accounts for electron corre...

[Phys. Rev. A 95, 063423] Published Tue Jun 27, 2017

]]>The SU(1,1) interferometer can be thought of as a Mach-Zehnder interferometer with its linear beam splitters replaced with parametric nonlinear optical processes. We consider the cases of bright- and vacuum-seeded SU(1,1) interferometers using intensity or homodyne detectors. A simplified truncated ...

[Phys. Rev. A 95, 063843] Published Tue Jun 27, 2017

]]>We propose a robust realization of the two-photon quantum Rabi model in a trapped-ion setting based on a continuous dynamical decoupling scheme. In this manner the magnetic dephasing noise, which is identified as the main obstacle to achieve long-time coherent dynamics in ion-trap simulators, can be...

[Phys. Rev. A 95, 063844] Published Tue Jun 27, 2017

]]>Photon pairs produced by parametric down-conversion or four-wave mixing can interfere with each other in multiport interferometers or carry entanglement between distant nodes for use in entanglement swapping. This requires the photons to be spectrally pure to ensure good interference and have high h...

[Phys. Rev. A 95, 061803(R)] Published Mon Jun 26, 2017

]]>In this paper we introduce an approach to Hamiltonian tomography of noninteracting tight-binding photonic lattices. To begin with, we prove that the matrix element of the low-energy effective Hamiltonian between sites $\alpha $ and $\beta $ may be obtained directly from ${S}_{\alpha \beta}\left(\omega \right)$, the (suitably normalized) two-port m...

[Phys. Rev. A 95, 062120] Published Mon Jun 26, 2017

]]>Quantum contextuality turns out to be a necessary resource for universal quantum computation and important in the field of quantum information processing. It is therefore of interest both for theoretical considerations and for experimental implementation to find new types and instances of contextual...

[Phys. Rev. A 95, 062121] Published Mon Jun 26, 2017

]]>We experimentally demonstrated an all-fiber-based unidimensional continuous-variable quantum key distribution (CV QKD) protocol and analyzed its security under collective attack in realistic conditions. A pulsed balanced homodyne detector, which could not be accessed by eavesdroppers, with phase-ins...

[Phys. Rev. A 95, 062330] Published Mon Jun 26, 2017

]]>A generalized and thorough investigation of entanglement without correlations is presented. The study sheds light on the different properties of systems composed of an even or odd number of qubits, and might help to construct computable measures of multipartite correlation.

[Phys. Rev. A 95, 062331] Published Mon Jun 26, 2017

]]>We consider the explicit construction of resource states for measurement-based quantum information processing. We concentrate on special-purpose resource states that are capable to perform a certain operation or task, where we consider unitary Clifford circuits as well as non-trace-preserving comple...

[Phys. Rev. A 95, 062332] Published Mon Jun 26, 2017

]]>The security of quantum key distribution (QKD) protocols hinges upon features of physical systems that are uniquely quantum in nature. We explore the role of quantumness, as qualified by quantum contextuality, in a QKD scheme. A QKD protocol based on the Klyachko-Can-Binicioğlu-Shumovsky (KCBS) cont...

[Phys. Rev. A 95, 062333] Published Mon Jun 26, 2017

]]>We present a family of quantum money schemes with classical verification which display a number of benefits over previous proposals. Our schemes are based on hidden matching quantum retrieval games and they tolerate noise up to $23\%$, which we conjecture reaches $25\%$ asymptotically as the dimension of ...

[Phys. Rev. A 95, 062334] Published Mon Jun 26, 2017

]]>The efficiency of optical trapping is determined by the atomic dynamic dipole polarizability, whose real and imaginary parts are associated with the potential energy and photon-scattering rate, respectively. In this article we develop a formalism to calculate analytically the real and imaginary part...

[Phys. Rev. A 95, 062508] Published Mon Jun 26, 2017

]]>In our previous work S. Bubin *et al.*, Chem. Phys. Lett. **647**, 122 (2016), it was established that complex explicitly correlated one-center all-particle Gaussian functions (CECGs) provide effective basis functions for very accurate nonrelativistic molecular non-Born-Oppenheimer calculations. In this ...

[Phys. Rev. A 95, 062509] Published Mon Jun 26, 2017

]]>We use accurate *ab initio* and quantum scattering calculations to explore the prospects for sympathetic cooling of the heavy molecular radical $\mathrm{SrOH}{(}^{2}{\mathrm{\Sigma}}^{+})$ by ultracold Li atoms in a magnetic trap. Our *ab initio* calculations show that the chemical reaction between spin-polarized Li and SrOH, which occur...

[Phys. Rev. A 95, 063421] Published Mon Jun 26, 2017

]]>We theoretically investigate trapping conditions for ultracold polar molecules in optical lattices when external magnetic and electric fields are simultaneously applied. Our results are based on an accurate electronic-structure calculation of the polar ${}^{23}\mathrm{Na}{}^{40}\mathrm{K}$ polar molecule in its absolute ground s...

[Phys. Rev. A 95, 063422] Published Mon Jun 26, 2017

]]>Thanks to their immense purity and controllability, dipolar Bose-Einstein condensates are an exemplar for studying fundamental nonlocal nonlinear physics. Here we show that a family of fundamental nonlinear waves—the dark solitons—are supported in trapped quasi-one-dimensional dipolar condensates an...

[Phys. Rev. A 95, 063622] Published Mon Jun 26, 2017

]]>We numerically show that time-delayed coherent feedback controls the statistical output characteristics of driven quantum emitters. Quantum feedback allows us to enhance or suppress a wide range of classical and nonclassical features of the emitted quantum light. As an exemplary quantum system, we u...

[Phys. Rev. A 95, 063840] Published Mon Jun 26, 2017

]]>In this paper, we address nonradiating and cloaking problems exploiting the surface equivalence principle, by imposing at any arbitrary boundary the control of the admittance discontinuity between the overall object (with or without cloak) and the background. After a rigorous demonstration, we apply...

[Phys. Rev. A 95, 063841] Published Mon Jun 26, 2017

]]>We present a study of collective multiphoton blockade in coherently driven atoms in a single-mode cavity. Considering two atoms strongly coupled to an optical cavity, we show that the two-photon blockade with two-photon antibunching, and the three-photon blockade with three-photon antibunching can b...

[Phys. Rev. A 95, 063842] Published Mon Jun 26, 2017

]]>[Phys. Rev. A 95, 069907] Published Mon Jun 26, 2017

]]>The Su-Schrieffer-Heeger (SSH) model lays the foundation of many important concepts in quantum topological matters. Here, we show that a spin-dependent double-well optical lattice allows one to couple two topologically distinct SSH chains in the bulk and realize a glided-two-leg SSH model that respe...

[Phys. Rev. A 95, 061601(R)] Published Fri Jun 23, 2017

]]>We study the long-time evolution of a quantum memory coupled to a bosonic environment on which quantum error correction (QEC) is performed using the surface code. The memory's evolution encompasses $N$ QEC cycles, each of them yielding a nonerror syndrome. This assumption makes our analysis independen...

[Phys. Rev. A 95, 062328] Published Fri Jun 23, 2017

]]>We derive a monogamy inequality for entanglement and local contextuality, for any finite bipartite system. It essentially results from the relations between the entropy of a local state and the entanglement of the global state, and between the purity of a state, in the sense of majorization, and its...

[Phys. Rev. A 95, 062329] Published Fri Jun 23, 2017

]]>We spectroscopically investigate the hyperfine, rotational, and Zeeman structure of the vibrational levels ${v}^{\prime}=0,7,13$ within the electronically excited $c{\phantom{\rule{0.222222em}{0ex}}}^{3}{\mathrm{\Sigma}}_{g}{}^{+}$ state of ${}^{87}\mathrm{Rb}_{2}$ for magnetic fields of up to $1000\phantom{\rule{0.28em}{0ex}}\text{G}$. As spectroscopic methods we use short-range photoassociation of ultracold Rb atoms as well a...

[Phys. Rev. A 95, 062507] Published Fri Jun 23, 2017

]]>We develop a theory of weakly interacting fermionic atoms in shaken optical lattices based on the orbital mixing in the presence of time-periodic modulations. Specifically, we focus on fermionic atoms in a circularly shaken square lattice with near-resonance frequencies, i.e., tuned close to the ene...

[Phys. Rev. A 95, 063619] Published Fri Jun 23, 2017

]]>We consider spin- and density-related properties of single-particle states in a one-dimensional system with random spin-orbit coupling. We show that the presence of an additional Zeeman field $\mathrm{\Delta}$ induces both nonlinear spin polarization and delocalization of states localized at $\mathrm{\Delta}=0$, corresponding to a...

[Phys. Rev. A 95, 063620] Published Fri Jun 23, 2017

]]>To explore the static properties of the one-dimensional anyon-Hubbard model for a mean density of one particle per site, we apply perturbation theory with respect to the ratio between kinetic energy and interaction energy in the Mott insulating phase. The strong-coupling results for the ground-state...

[Phys. Rev. A 95, 063621] Published Fri Jun 23, 2017

]]>Predictions of diffraction patterns for honeycomb photonic crystals were part of a comprehensive study of these structures that may be useful in nanoscale photonic devices.

[Phys. Rev. A 95, 063837] Published Fri Jun 23, 2017

]]>A full propagation analysis on both fold-type and cusp-type caustic optical beams under various setups of obstructions is theoretically and experimentally performed. It is demonstrated that the self-healing property of caustic optical beams that include the famous Airy beam is a quite relative prope...

[Phys. Rev. A 95, 063838] Published Fri Jun 23, 2017

]]>Light scattering is one of the most important elementary processes in near-field optics. We build up the Born series for scattering by dielectric bodies with sharp boundaries. The Green's function for a two-dimensional homogeneous dielectric cylinder is obtained. As an example, the formulas are deri...

[Phys. Rev. A 95, 063839] Published Fri Jun 23, 2017

]]>[Phys. Rev. A 95, 069906] Published Fri Jun 23, 2017

]]>We demonstrate the breakdown of molecular-frame dynamics induced by the uncoupling of molecular rotation from electronic motion in molecular Rydberg states. We observe this non-Born-Oppenheimer regime in the time domain through photoelectron imaging of a coherent molecular Rydberg wave packet in ${\mathrm{N}}_{2}$....

[Phys. Rev. A 95, 061403(R)] Published Thu Jun 22, 2017

]]>We investigate the Anderson localization in non-Hermitian Aubry-André-Harper (AAH) models with imaginary potentials added to lattice sites to represent the physical gain and loss during the interacting processes between the system and environment. By checking the mean inverse participation ratio (MI...

[Phys. Rev. A 95, 062118] Published Thu Jun 22, 2017

]]>The broad success of theoretical and experimental quantum optimal control is intimately connected to the topology of the underlying control landscape. For several common quantum control goals, including the maximization of an observable expectation value, the landscape has been shown to lack local o...

[Phys. Rev. A 95, 063418] Published Thu Jun 22, 2017

]]>We propose an intuitive method, called the time-dependent population imaging (TDPI) method, to map the dynamical processes of high-order-harmonic generation (HHG) in solids by solving the time-dependent Schrödinger equation. It is shown that the real-time dynamical characteristics of HHG in solids, ...

[Phys. Rev. A 95, 063419] Published Thu Jun 22, 2017

]]>We consider harmonic generation from a semiconductor described in the two-band approximation. In particular, the signatures of the Floquet-Bloch states in the low-order harmonic spectra are studied. We find field-strength-dependent shifts of the position of resonant peaks. The shifts are analogous t...

[Phys. Rev. A 95, 063420] Published Thu Jun 22, 2017

]]>Surface scattering of neutral helium beams created by supersonic expansion is an established technique for measuring structural and dynamical properties of surfaces on the atomic scale. Helium beams have also been used in Fraunhofer and Fresnel diffraction experiments. Due to the short wavelength of...

[Phys. Rev. A 95, 063618] Published Thu Jun 22, 2017

]]>We explore, both experimentally and theoretically, the propagation dynamics of spatially entangled photon pairs (biphotons). Characterization of entanglement is done via the Schmidt number, which is a universal measurement of the degree of entanglement directly related to the nonseparability of the ...

[Phys. Rev. A 95, 063836] Published Thu Jun 22, 2017

]]>It has been found via numerical simulations that the geometric phase (GP) and fidelity susceptibility (FS) across the quantum critical points exhibit some universal scaling laws. Here we propose a singular function expansion method to find their exact singular forms and the related coefficients acro...

[Phys. Rev. A 95, 062117] Published Wed Jun 21, 2017

]]>We study transient charges formed in methane clusters following ionization by intense near-infrared laser pulses. Cluster ionization by 400-fs ($I=1\times {10}^{14}\mathrm{W}/{\mathrm{cm}}^{2}$) pulses is highly efficient, resulting in the observation of a dominant ${\mathrm{C}}^{3+}$ ion contribution. The ${\mathrm{C}}^{4+}$ ion yield is very small but is strongly...

[Phys. Rev. A 95, 063417] Published Wed Jun 21, 2017

]]>We explore the topological properties of double-Weyl semimetals with cold atoms in optical lattices. We first propose a tight-binding model of simulating the double-Weyl semimetal with a pair of double-Weyl points by engineering the atomic hopping in a three-dimensional optical lattice. We show that...

[Phys. Rev. A 95, 063616] Published Wed Jun 21, 2017

]]>Spin-orbit coupling (SOC) is at the heart of many exotic band structures and can give rise to many-body states with topological order. Here we present a general scheme based on a combination of microwave driving and lattice shaking for the realization of two-dimensional SOC with ultracold atoms in s...

[Phys. Rev. A 95, 063617] Published Wed Jun 21, 2017

]]>We analyze the stability of a non-Hermitian coupler with respect to modulational inhomogeneous perturbations in the presence of unbalanced gain and loss. At the parity-time ($\mathcal{PT}$) symmetry point the coupler is unstable. Suitable symmetry breakings lead to an asymmetric coupler, which hosts nonlinear s...

[Phys. Rev. A 95, 063832] Published Wed Jun 21, 2017

]]>Polarizability expressions are commonly used in optics and photonics to model light scattering by small particles. Models based on Taylor series of the scattering coefficients of the particles fail to predict the morphologic resonances hosted by dielectric particles. Here we propose to use the facto...

[Phys. Rev. A 95, 063833] Published Wed Jun 21, 2017

]]>We experimentally demonstrate two types of peak-peak delay effects in linear and high-gain saturation regions of a stimulated Raman process in ${}^{87}\mathrm{Rb}$ atomic vapor. The delay time linearly increases with the intensity of the Raman pump field in the linear Raman amplifier due to the slow-light effect bu...

[Phys. Rev. A 95, 063834] Published Wed Jun 21, 2017

]]>We revisit the notion of nonclassical distance of states of bosonic quantum systems introduced in Phys. Rev. A **35**, 725 (1987) in a general multimode setting. After reviewing its definition, we establish some of its general properties. We obtain new upper and lower bounds on the nonclassical distance...

[Phys. Rev. A 95, 063835] Published Wed Jun 21, 2017

]]>Tensor network states are for good reasons believed to capture ground states of gapped local Hamiltonians arising in the condensed matter context, states which are in turn expected to satisfy an entanglement area law. However, the computational hardness of contracting projected entangled pair states...

[Phys. Rev. A 95, 060102(R)] Published Tue Jun 20, 2017

]]>We report calculations of the one-loop self-energy correction to the bound-electron $g$ factor of the $1s$ and $2s$ states of light hydrogenlike ions with a nuclear charge number $Z\le 20$. The calculation is carried out to all orders in the binding nuclear strength. We find good agreement with previous calcul...

[Phys. Rev. A 95, 060501(R)] Published Tue Jun 20, 2017

]]>We present a theoretical study of entanglement in ensembles consisting of an arbitrary number of particles. Multipartite entanglement criteria in terms of observables are formulated for a fixed number of particles as well as for systems with a fluctuating particle number. To access the quality of th...

[Phys. Rev. A 95, 062116] Published Tue Jun 20, 2017

]]>We generalize the recently proposed resource theory of coherence (or superposition) [T. Baumgratz *et al.*, Phys. Rev. Lett. **113**, 140401 (2014); A. Winter and D. Yang, Phys. Rev. Lett. **116**, 120404 (2016)] to the setting where not just the free (“incoherent”) resources, but also the manipulated object...

[Phys. Rev. A 95, 062327] Published Tue Jun 20, 2017

]]>We present a combined theoretical and experimental study of the energy loss of ${\mathrm{H}}_{2}{}^{+}$ molecular ions interacting with thin oxide and carbon films. As a result of quantum mechanical interference of the target electrons, the energy loss of a molecular projectile differs from the sum of the energy losses ...

[Phys. Rev. A 95, 062707] Published Tue Jun 20, 2017

]]>Quantum systems depending on parameters may have exceptional points (EPs) in the parameter space where complex energies of their resonance states coalesce. Here we show that electronic Siegert states of molecules in a static electric field have EPs in the internuclear distance—field strength plane. ...

[Phys. Rev. A 95, 063416] Published Tue Jun 20, 2017

]]>We present gap solitons (GSs) that can be created in free nearly two-dimensional (2D) space in dipolar spinor Bose-Einstein condensates with the spin-orbit coupling (SOC), subject to tight confinement, with size ${a}_{\perp}$, in the third direction. For quasi-2D patterns, with lateral sizes $l\gg {a}_{\perp}$, the kinetic-...

[Phys. Rev. A 95, 063613] Published Tue Jun 20, 2017

]]>We study a single quantized vortex in the fermionic component of a mixture of Fermi superfluid and Bose-Einstein condensate. As the density ratio between the boson and the fermion components is tuned, we identify a transition in the vortex-core structure, across which fermions in the vortex core bec...

[Phys. Rev. A 95, 063614] Published Tue Jun 20, 2017

]]>We present an in-depth study of the nonequilibrium statistics of the irreversible work produced during sudden quenches in proximity to the structural linear-zigzag transition of ion Coulomb crystals in 1+1 dimensions. By employing both an analytical approach based on a harmonic expansion and numeric...

[Phys. Rev. A 95, 063615] Published Tue Jun 20, 2017

]]>The photonic spin Hall effect (SHE) can be regarded as a direct optical analogy of the SHE in electronic systems where a refractive index gradient plays the role of an electric potential. However, it has been demonstrated that the effective refractive index fails to adequately explain the light-matt...

[Phys. Rev. A 95, 063827] Published Tue Jun 20, 2017

]]>We theoretically study the transparency in the generalized two-level system with hyperfine structure by utilizing double detuning-induced stimulated Raman adiabatic passage (double D-STIRAP). The double D-STIRAP is carried out by sequentially applying the three pulses, one near-resonant pump pulse a...

[Phys. Rev. A 95, 063828] Published Tue Jun 20, 2017

]]>We introduce spatial deformations to an array of light sources and study how the estimation precision of the interspacing distance $d$ changes with the sources of light used. The quantum Fisher information (QFI) is used as the figure of merit in this work to quantify the amount of information we have ...

[Phys. Rev. A 95, 063829] Published Tue Jun 20, 2017

]]>There are two opposing models in the analysis of the slow transmission of light pulses through saturable absorbers. The canonical incoherent bleaching model simply explains the slow transmission by combined effects of saturation and of noninstantaneous response of the medium resulting in absorption ...

[Phys. Rev. A 95, 063830] Published Tue Jun 20, 2017

]]>Terahertz time-domain spectroscopy is increasingly used in many fields of research. For strongly absorbing materials with refraction index close to 1, optical parameters at terahertz frequencies are most conveniently quantified using transmission measurements through thin samples. Unfortunately, ext...

[Phys. Rev. A 95, 063831] Published Tue Jun 20, 2017

]]>Assuming the standard axioms for quaternionic quantum theory and a spatially localized scattering interaction, the $S$ matrix in quaternionic quantum theory is complex valued, not quaternionic. Using the standard connections between the $S$ matrix, the forward scattering amplitude for electromagnetic wa...

[Phys. Rev. A 95, 060101(R)] Published Mon Jun 19, 2017

]]>Quantum states of light having a Wigner function with negative values represent a key resource in quantum communication and quantum information processing. Here we present the generation of such a state at the telecommunication wavelength of 1550 nm. The state is generated by means of photon subtrac...

[Phys. Rev. A 95, 061802(R)] Published Mon Jun 19, 2017

]]>We study the thermalization of an ensemble of $N$ elementary, arbitrarily complex, quantum systems, mutually noninteracting but coupled as electric or magnetic dipoles to a blackbody radiation. The elementary systems can be all the same or belong to different species, distinguishable or indistinguisha...

[Phys. Rev. A 95, 062112] Published Mon Jun 19, 2017

]]>We study the properties of Hamiltonians defined as the generators of transfer matrices in quasi-one-dimensional waveguides. For single- or multimode waveguides obeying flux conservation and time-reversal invariance, the Hamiltonians defined in this way are non-Hermitian, but satisfy symmetry propert...

[Phys. Rev. A 95, 062113] Published Mon Jun 19, 2017

]]>Anderson localization is a consequence of coherent interference of multiple scattering events in the presence of disorder, which leads to an exponential suppression of the transmission. The decay of the transmission is typically probed at a given energy or frequency. Here we show that this decay aff...

[Phys. Rev. A 95, 062114] Published Mon Jun 19, 2017

]]>In this paper we consider the excitation of one quantum dipole by another in the deep quantum limit. We use a full quantum mechanical theory to describe the interaction of the dipoles through the electromagnetic field. Our nonperturbative analytical calculations result in the exact solution. We show...

[Phys. Rev. A 95, 062115] Published Mon Jun 19, 2017

]]>The single-electron detachment (SED) cross sections of $\mathrm{F}{\mathrm{e}}^{-}$, $\mathrm{R}{\mathrm{u}}^{-}$, $\mathrm{N}{\mathrm{i}}^{-}$, $\mathrm{P}{\mathrm{d}}^{-}$, and $\mathrm{P}{\mathrm{t}}^{-}$ in collisions with inert-gas atoms are measured by using the growth-rate method. The projectile energy ranges from 10 to 30 keV. The cross sections increase as the impact velocity increases. For anions in the same ele...

[Phys. Rev. A 95, 062706] Published Mon Jun 19, 2017

]]>Two-photon ionization of xenon was investigated theoretically for exciting-photon energies from 6.7 to 11.5 eV, which results in the ionization of Xe between $5{p}_{1/2}$ (13.43 eV) and $5s$ (23.40 eV) thresholds. We describe the extension of a previously developed computational technique for the inclusion o...

[Phys. Rev. A 95, 063414] Published Mon Jun 19, 2017

]]>Experimental and theoretical investigations of the wavelength dependence of the nonsequential double ionization (NSDI) process of the xenon atom in intense laser fields are reported. The observed wavelength dependence of the ratio ${\mathrm{Xe}}^{2+}/{\mathrm{Xe}}^{+}$ deviates significantly from the prediction of the three-step...

[Phys. Rev. A 95, 063415] Published Mon Jun 19, 2017

]]>We study the Bose-Einstein condensation of photons in a plasma, where we include the cases of both transverse photons and plasmons. We consider four-wave mixing processes of photon and plasmon modes in a relativistic isotropic plasma to determine the coupling constant to lowest order. We further sho...

[Phys. Rev. A 95, 063611] Published Mon Jun 19, 2017

]]>An innovative way to produce quantum Hall ribbons in a cold atomic system is to use $M$ hyperfine states of atoms in a one-dimensional optical lattice to mimic an additional “synthetic dimension.” A notable aspect here is that the SU($M$) symmetric interaction between atoms manifests as “infinite ranged...

[Phys. Rev. A 95, 063612] Published Mon Jun 19, 2017

]]>In nonlinear fiber systems operating in pulsed regime, the pumping excitation is no longer time extended (cw regime) but localized in time with a finite duration. In this case, standard linear stability analysis (often called modulational instability), as it stands, fails to describe the linear time...

[Phys. Rev. A 95, 063826] Published Mon Jun 19, 2017

]]>We study the properties of bisqueezed tripartite Gaussian states created by two spontaneous parametric down-conversion processes that share a common idler. We give a complete description of the quantum correlations across all partitions, as well as of the genuine multipartite entanglement, obtaining...

[Phys. Rev. A 95, 062324] Published Fri Jun 16, 2017

]]>How to effectively construct robust quantum gates for time-varying noise is a very important but still outstanding problem. Here we develop a systematic method to find pulses for quantum gate operations robust against both low- and high-frequency (comparable to the qubit transition frequency) stocha...

[Phys. Rev. A 95, 062325] Published Fri Jun 16, 2017

]]>Quantum walks and random walks bear similarities and divergences. One of the most remarkable disparities affects the probability of finding the particle at a given location: typically, almost a flat function in the first case and a bell-shaped one in the second case. Here I show how one can impose a...

[Phys. Rev. A 95, 062326] Published Fri Jun 16, 2017

]]>We study the two-body scattering problem in the zero-range approximation with a sinusoidally driven scattering length and calculate the relation between the mean value and amplitude of the drive for which the effective scattering amplitude is resonantly enhanced. In this manner we arrive at a family...

[Phys. Rev. A 95, 062705] Published Fri Jun 16, 2017

]]>Fulde-Ferrell (FF) Larkin-Ovchinnikov (LO) phases were proposed for superconductors or superfluids in a strong magnetic field. With the experimental progress in ultracold atomic systems, topological FFLO phases have also been put forward since it is a natural consequence of realizable spin-orbital c...

[Phys. Rev. A 95, 063610] Published Fri Jun 16, 2017

]]>We provide a theory for quantum-optical realizations of the open Dicke model with internal, atomic spin states subject to spontaneous emission with rate $\gamma $. This introduces a second decay channel for excitations to irreversibly dissipate into the environment, in addition to the photon loss with rate $\mathrm{...}$

[Phys. Rev. A 95, 063824] Published Fri Jun 16, 2017

]]>We explore the optomechanically induced absorption (OMIA) in a parity-time- ($\mathcal{PT}$-) symmetric optomechanical system (OMS). By numerically calculating the Lyapunov exponents, we find out the stability border of the $\mathcal{PT}$-symmetric OMS. The results show that in the $\mathcal{PT}$-symmetric phase the system can be eith...

[Phys. Rev. A 95, 063825] Published Fri Jun 16, 2017

]]>We report molecular-frame electron-scattering cross sections of ${\mathrm{N}}_{2}$, obtained using an electron-ion coincidence technique. Vector correlation between the scattered electron and the fragment ion has been measured at incident electron energy of 1.4 keV for the dipole-forbidden $2{\sigma}_{g}\to 1{\pi}_{g}$ transition of ${\mathrm{N}}_{2}$ ...

[Phys. Rev. A 95, 060702(R)] Published Thu Jun 15, 2017

]]>Einstein-Podolsky-Rosen (EPR) steering is an intermediate type of quantum nonlocality which sits between entanglement and Bell nonlocality. A set of correlations is Bell nonlocal if it does not admit a local hidden variable (LHV) model, while it is EPR nonlocal if it does not admit a local hidden va...

[Phys. Rev. A 95, 062111] Published Thu Jun 15, 2017

]]>We consider the problem of certifying binary observables based on a Bell inequality violation alone, a task known as *self-testing of measurements*. We introduce a family of commutation-based measures, which encode all the distinct arrangements of two projective observables on a qubit. These quantitie...

[Phys. Rev. A 95, 062323] Published Thu Jun 15, 2017

]]>The rotational and hyperfine spectrum of the $X{\phantom{\rule{0.16em}{0ex}}}^{1}{\mathrm{\Sigma}}^{+}\to B{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{\Pi}}_{1}$ transition in TlF molecules was measured using laser-induced fluorescence from both a thermal and a cryogenic molecular beam. Rotational and hyperfine constants for the $B$ state are obtained. The large magnetic hyperfine interaction of the Tl nuc...

[Phys. Rev. A 95, 062506] Published Thu Jun 15, 2017

]]>We investigate the prospects of using magnetic Feshbach resonance to control charge exchange in ultracold collisions of heteroisotopic combinations of atoms and ions of the same element. The proposed treatment, readily applicable to alkali or alkaline-earth metals, is illustrated on cold collisions ...

[Phys. Rev. A 95, 062704] Published Thu Jun 15, 2017

]]>We perform time-resolved UV pump (4.77 eV) and VUV probe (7.94 eV) measurements of internal conversion of 1,3-cyclohexadiene (CHD). Our measurements reveal a substantial ionization of the “hot” ground state following internal conversion despite the fact that our probe photon energy is below the ioni...

[Phys. Rev. A 95, 063413] Published Thu Jun 15, 2017

]]>Two distinct regimes of supersolid order are found in the ground-state phase diagram of a two-dimensional Rydberg lattice gas, where the regimes are dominated by either weak or strong dressing, reminiscent of the bistable behavior in nonitinerant dissipative systems.

[Phys. Rev. A 95, 063608] Published Thu Jun 15, 2017

]]>We study theoretically the interaction-induced generation of mesoscopic coherent spin state superpositions (small-particle-number cat states) from an initial coherent spin state in bimodal Bose-Einstein condensates and the subsequent phase revival, including decoherence due to particle losses and fl...

[Phys. Rev. A 95, 063609] Published Thu Jun 15, 2017

]]>The fluctuations or disordered motion of the electromagnetic fields are described by statistical properties rather than instantaneous values. This statistical description of the optical fields is underlying in the Stokes-Mueller formalism that applies to measurable intensities. However, the fundamen...

[Phys. Rev. A 95, 063819] Published Thu Jun 15, 2017

]]>We investigate the peculiarities of light scattering from subwavelength particles made of high-refractive-index materials caused by the coexistence of particular anapole modes of both electric and magnetic character. The similarities and differences of such anapole modes are discussed in detail. We ...

[Phys. Rev. A 95, 063820] Published Thu Jun 15, 2017

]]>When measuring a time-varying phase, the standard quantum limit and Heisenberg limit as usually defined, for a constant phase, do not apply. If the phase has Gaussian statistics and a power-law spectrum $1/{\left|\omega \right|}^{p}$ with $p>1$, then the generalized standard quantum limit and Heisenberg limit have recentl...

[Phys. Rev. A 95, 063821] Published Thu Jun 15, 2017

]]>We previously demonstrated near-field speckle-scanning-based x-ray imaging to be an easy-to-implement phase-sensing method capable of providing both high sensitivity and high resolution. Yet this performance combination could only be achieved at the cost of a significant number of sample exposures a...

[Phys. Rev. A 95, 063822] Published Thu Jun 15, 2017

]]>In this work we study the impact of chromatic focusing of few-cycle laser pulses on high-order-harmonic generation (HHG) through analysis of the emitted extreme ultraviolet (XUV) radiation. Chromatic focusing is usually avoided in the few-cycle regime, as the pulse spatiotemporal structure may be hi...

[Phys. Rev. A 95, 063823] Published Thu Jun 15, 2017

]]>Rains' bound is arguably the best known upper bound of the distillable entanglement by operations completely preserving positivity of partial transpose (PPT) and was conjectured to be additive and coincide with the asymptotic relative entropy of entanglement. We disprove both conjectures by explicit...

[Phys. Rev. A 95, 062322] Published Wed Jun 14, 2017

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