Newsfeeds

Journal of Physics B: Atomic, Molecular and Optical Physics - latest papers

Latest articles for Journal of Physics B: Atomic, Molecular and Optical Physics

IOPscience

  • Towards metrology with highly charged isomeric ions from antiproton annihilation
    We describe how the annihilation of antiprotons can be utilized to generate highly charged isomeric ions in an ion-trap setup. We identify optical transitions in the hyperfine (HF) splitting of Hydrogen-like atoms composed of an isomer and a single electron in the ground state. We identify promising candidates in the isomers of Y, Nb, Rh, In, and Sb, for which the HF transition lies in the infrared and whose excited state level lifetime is in the hundreds of milliseconds, which is suitable for metrology applications.

  • Enhanced entanglement of a two-mode squeezed vacuum state via a state-projective operation and a phase measurement
    This paper aims to substantially enhance the entanglement of the two-mode squeezed vacuum state (TMSVS) by proposing a new state engineered through a sequential application of a state-projective operation followed by a phase measurement (PM). This construction exploits a laser field modeled as a coherent state of moderately strong amplitude, thereby compensating for the limited squeezing achievable in practice. Remarkably, the resulting state achieves entanglement, quantified by the von Neumann entropy, exceeding 3.45 even for moderate squeezing ( ), whereas it remains below 1.22 for the TMSVS. In addition, we show that the state can teleport a coherent state with an average fidelity exceeding 99%. Finally, we propose an optical scheme for generating the new state. In addition to the PM element, the scheme employs three weak cross-Kerr nonlinear media, two beam splitters, and a nonideal on-off photodetector. The proposed state can be utilized for quantum information processing, particularly in continuous-variable quantum circuits involving entanglement.

  • Comparison between Jacobi–Anger and saddle point methods to treat above-threshold ionization
    We present a detailed comparison of theoretical approaches for modeling strong-field ionization by few-cycle laser pulses. The dipole approximation is shown to accurately capture interference structures in photoelectron spectra, while non-dipole effects introduce significant momentum shifts along the propagation direction. Two complementary analytical methods are used: the Jacobi–Anger expansion provides complete spectral decomposition of transition amplitudes, whereas the saddle-point method efficiently identifies dominant ionization pathways. Through this comparative study within the strong-field approximation framework, we establish validity conditions and practical advantages for each approach. Our results provide guidelines for selecting theoretical methods for advancing the interpretation of strong-field processes. These findings provide a roadmap for interpreting strong-field ionization spectra and momentum distributions, highlighting where non-dipole effects and method choice critically alter predictions.

  • Self-adaptive stochastic basis in the Schwinger variational framework with an application to positron-atom scattering
    We present a self-adaptive stochastic basis strategy within the Schwinger Variational Principle framework for low-energy positron-atom scattering. The method constructs compact, system-tailored basis sets using uncorrelated Slater-type orbitals selected via rejection sampling, guided by physical coupling strengths. This correlation-free approach efficiently captures essential scattering dynamics, both short- and long-range, without the need for explicit electron–positron correlation terms. As a benchmark, we apply the method to positron-hydrogen collisions and compute the s-wave scattering length and zero-energy annihilation parameter, obtaining and , in excellent agreement with high-precision literature values. Extensive convergence and statistical analyses confirm the method’s accuracy, robustness, and fast convergence. The generality and low computational cost of the approach make it a promising tool for high-precision scattering calculations in atomic and molecular systems.

  • Distribution and revival of tripartite Einstein–Podolsky–Rosen steering in all-optical correlated noise channel
    Quantum steering, also know as Einstein–Podolsky–Rosen steering, is a key resource in quantum information. It has significant application value for constructing secure quantum communication networks due to its unique asymmetric property. However, quantum steering is susceptible to decoherence. Decoherence occurs due to the interaction between a quantum system and its environment, and eventually leads to the reduction or even disappearance of steering. In this paper, we propose an all-optical correlated noise channel (ACNC) scheme based on four-wave mixing (FWM) processes, investigate the impact of noise in the channel and FWM gains on quantum steering characteristics as well as the capability of the ACNC to restore quantum steering. This scheme is achieved through optical nonlinear processes and avoids the electro-optic conversions and significantly expands the operational bandwidth. The research results show that the ACNC can effectively restore the damaged quantum steering. The range of one-way steering and genuine tripartite steering can be flexibly controlled by adjusting parameters. Moreover, the Gaussian steered monogamous relationships have also been verified. Our scheme provides new theoretical reference for constructing all-optical secure quantum networks.