Annalen der Physik最新文献

Topological insulators are characterized by protected gapless surface or edge states but insulating bulk states which is due to the presence of spin-orbit interactions and time-reversal symmetry. Here, an in-depth investigation of a topological nodal line semimetal PbTaSe₂ via temperature, polarization dependent Raman spectroscopy, and temperature dependent single crystal X-ray diffraction (SC-XRD) measurements is reported. The analysis shows signature of electron-phonon coupling as reflected in the Fano asymmetry in line shape of M1-M4 modes and anomalous temperature variation of line-width of P3-P4 modes. Further polarization dependent phonon symmetry changes at different temperature (6K and 300K), discontinuities in bulk phonon dynamics for P2-P5 modes, and disappearance of phonon modes, i.e., M1-M5, on decreasing temperature indicates toward a thermally induced structural phase transition which is also supported by the SC-XRD results. Hence based on the findings, it is proposed that M1-M4 modes are surface phonon modes, the material undergoes a thermally induced structural phase transition from α to β phase at T_α→β ≈ 150 K or is in close proximity to the β phase and another transition below T_CDW+β ≈ 100K which is possibly due to the interplay of remanent completely commensurate charge density wave (CCDW) of 1H-TaSe₂ and β phase.

Negative-Mass Black Holes under Antichronous Transformations

Black hole's gravitational singularities are solved by interior negative energies and masses through time transformations of relativistic quantum mechanics and antichronous transformations of the full Lorentz group, which, if taking place at event horizons, respect Einstein's equivalence principle. For further details, see article number 2400139 by Manuel Uruena Palomo.

Enhancement of Quantum Entanglement in Cavity–Magnon systems

In article number 2400221, Rong-Can Yang, Hong-Yu Liu, and co-workers focus on the enhancement of quantum entanglement and quantum steering in cavity–magnon hybrid systems using quantum coherent feedback (QCFB) control loops, as shown in the cover image. In the scheme, SQUID is applied to realize Josephson parametric amplification, driving the 3D microwave cavity with two-photon field. Moreover, quantum correlation of the two magnon modes is indirectly established through the magnetic dipole interaction, and the enhancement is implemented effectively with QCFB.

Pengfei Wang, Lei Huang, Hanxiao Zhang, Hong Yang, and Dong Yan. Unconventional Light-Matter Interactions Between Giant Atoms and Structured Baths with Next-Nearest-Neighbor Coplings. Annalen der Physik (Berlin), 2024, 536, 2400165.

https://doi.org/10.1002/andp.202400165

The first affiliation of all authors is incorrect. It should read: “College of Physics and Electronic Engineering, Hainan Normal University, Haikou 571158, P. R. China.”

We apologize for this error.

The quantum entanglement and the one-way quantum steering in cavity magnonic system composed of a yttrium iron garnet (YIG) sphere and two microwave cavities, one of which is driven by a two-photon drive field, are studied. Bipartite entanglement, tripartite entanglement, and steering can be achieved under the four-wave mixing process. It is shown that the degree of entanglement and the direction of one-way steering can be manipulated not only by designing the dissipation ratio between the two cavity modes but also by regulating the coherent coupling strength ratio between the two cavity modes and the magnon mode. It is found that the direction of steering is associated with the populations of the two cavity modes, meaning that the mode with a greater population always dominates the steering direction. Especially, the transfer between cavity–magnon entanglement and cavity–cavity entanglement can be realized by adjusting the coupling strengths. The findings provide a practical method for coherently manipulating entanglement and one-way steering in cavity–magnon system.

The Hong-Ou-Mandel interference of two identical particles evolving on a 1D tight-binding lattice where a potential barrier plays the role of a beam splitter is described. Careful consideration of the symmetries underlying the two-particle interference effect allows to reformulate the problem in terms of ordinary wave interference in a Michelson interferometer. This approach is easily generalized to the case where the particles interact, and we compare the resulting analytical predictions for the bunching probability to numerical simulations of the two-particle dynamics.

Studies of the effects of the weak interaction in atomic systems provide tests of the Standard Model of particle physics, and explore physics scenarios beyond the Standard Model. In addition, these studies can offer valuable insights into low-energy nuclear physics. An overview of the field of atomic parity violation is provided, and implications to nuclear and particle physics and ongoing experimental efforts are discussed. Furthermore, the plans for precision measurements of the signatures of the weak interaction in atomic ytterbium are discussed.

This study tackles critical issues in semi-quantum signature (SQS) protocols to enhance security and efficiency. It revisits Xia et al.’s SQS protocol, which uses EPR steering for security but introduces inconsistencies in a semi-quantum environment. Xia et al. assume that both the signatory and arbitrator have full quantum capabilities, while the verifier only has partial capabilities, making them a classical participant. However, their protocol requires the verifier to perform eavesdropping checks, necessitating quantum storage, which is not aligned with a semi-quantum environment. The study proposes a novel SQS protocol using EPR steering and single photons, with pre-shared keys to determine photon arrangements to address this. This ensures that only the communicating parties know the inspection and message transmission locations, solving the quantum storage issue and enabling efficient eavesdropper detection and identity authentication. This new protocol adheres to semi-quantum principles and sets a foundation for future advancements in quantum cryptography and secure communication.