Annalen der Physik最新文献

Micro-nano technology and material science have rapidly evolved, and they lead to the emergence of metasurface. However, there are scarce studies on multi-channel metasurface to generate orbital angular momentum (OAM) and grayscale image (GI) simultaneously. In this work, the metasurface introduces Malus’ law and spin decoupling to modulate terahertz wavefronts. The designed metasurface consists of the following layers from top to bottom: VO₂ patches, silica spacer, gold patches embedded in the VO₂ layer, silica spacer, and gold substrate. For high-conductivity VO₂ exhibiting a metallic state, the VO₂ metasurface achieves a vortex beam (VB) with topological charge (TC) of l = 1 under right-handed circularly polarized (RCP) incidence, and it obtains a VB with a gradient phase and $���\mathrm{TC}���=�2�$ under left-handed circularly polarized (LCP) incidence. Meanwhile, GI B is observed in the near field under y-polarized incidence. For low-conductivity VO₂ exhibiting an insulating state, the gold structure embedded in the VO₂ film takes control of the electromagnetic wave. Metasurface obtains a VB with a gradient phase and $���\mathrm{TC}���=�-�1�$ in the LCP channel, and it achieves a VB with $���\mathrm{TC}���=�-�2�$ in the RCP channel. Simultaneously, GI A is shown in the near field under y-polarized incidence. The vast potential of metasurface for applications in imaging and information processing is demonstrated.

The search for zero-gap spin-polarized materials such as spin-gapless semiconductors (SGSs) and their interplay with topological phases is of central importance for realizing dissipationless spintronic functionalities, with the quantum anomalous Hall (QAH) effect being a particularly appealing target. Kagome lattices provide a natural platform for such physics owing to their possible Weyl-like dispersions and strong correlation effects. Here, by first-principle calculations, the kagome-lattice Zn₂N₃ monolayer is identified as a 2D linear SGS that hosts intrinsic ferromagnetism with a Curie temperature of 204 K. In the absence of spin–orbit coupling (SOC), the system exhibits spin-down Weyl-like crossings and spin-up gap at the Fermi level with complete spin polarization. SOC lifts these degeneracies, opening a topological gap and inducing an intrinsic QAH state with Chern number 𝐶 = 1 and chiral edge states, which remain stable under biaxial strain up to 10%. These results establish Zn₂N₃ as a robust platform for next-generation spintronic and topological quantum devices with ultralow energy dissipation.

Axions are considered a key component of dark matter, characterized by very weak couplings to fermions and Chern-Simons couplings to gauge fields. We propose a novel detection mechanism based on symmetry-breaking magnetoelectric materialswith a linear axionic coupling between magnetism and ferroelectric polarization. The focus is on a strain gradient $$ film, where the breaking of space-inversion symmetry results in an emergent polar phase and out-of-plane magnetic moment, exhibiting a flexomagnetoelectric effect. In this material, the linear $$ enables a direct coupling between the external axion field and the intrinsic axion-like field, which amplifies the weak electromagnetic signals induced by axions, paving the way for pioneering axion detection. These signals can be detected by monitoring changes in macroscopic physical quantities, such as the magnetoelectric and magnetic responses. In contrast to conventional detection techniques, this mechanism is expected to enhance the sensitivity of the axion-electron and axion-photon coupling, providing a novel platform for axion detection and advancing the study of dark matter through the magnetoelectric effect.

Vector vortex beams, featuring spatially structured polarization states and helical phase fronts, emerge as a critical solution for enhancing optical information capacity beyond the constraints of traditional communication paradigms. In this paper, a coherent modulation strategy is established for creating two dimension (2D) vector vortex far-field diffraction arrays through light-atom interactions under electromagnetically induced transparency (EIT). A dynamically reconfigurable optical lattice is engineered via interference between a Gaussian-coupled field and a vortex-coupled field with adjustable topological charge. The atomic medium, when subjected to this lattice modulation, facilitates the diffraction of probe vector light fields into high-order vector vortex diffracted spots. This system enables multi-parameter tuning to significantly enhance diffraction efficiency. Results demonstrate that Comprehensive optimization of coupling field intensity, interference beam power distribution, and frequency detuning significantly enhances the relative diffraction efficiency. Moreover, the polarization state distribution of diffraction fields can be reconfigured by controlling optical lattice topological charges. This atomic medium-based optical lattice modulation framework offers flexibility in tailoring structured light arrays, bridging fundamental studies of structured light-matter interactions with advanced applications in high-dimensional optical encoding, quantum state engineering, and multifunctional optical manipulation systems.

It is demonstrated how a set of particle representations, familiar from the Standard Model, collectively form a superalgebra. Those representations mirroring the behavior of the Standard Model's gauge bosons, and three generations of fermions, are each included in this algebra, with exception only to those irreps involving the top quark. This superalgebra is isomorphic to the Euclidean Jordan algebra of $$ hermitian matrices, $$, and is generated by division algebras. The division algebraic substructure enables a natural factorization between internal and spacetime symmetries. It also allows for the definition of a $$ grading on the algebra. Those internal symmetries respecting this substructure are found to be $$, in addition to four iterations of $$. For spatial symmetries, one finds multiple copies of $$. Given its Jordan algebraic foundation, and its apparent non-relativistic character, the model may supply a bridge between particle physics and quantum computing. We close by describing how this article fits into the larger picture of Bott Periodic Particle Physics, first introduced in 2014, 2021, 2023.

The certain quantumness in the vicinity of the Schwarzschild black hole is investigated by utilizing the W state. The influence of the Hawking effect on the $�l_1$-norm of quantum coherence, first-order coherence (FOC) is explored, concurrence-fill (CF) and global concurrence (GC) in Schwarzschild black hole, for systems with one, two and three physically accessible modes. It is concluded that the Hawking effect not only perturbs but also amplifies the quantum entanglement, while destroying the quantum coherence for systems with three physically accessible modes. For systems with one or two physically accessible modes, the Hawking effect has a beneficial effect on quantum coherence and entanglement. Moreover, the influence of both the Hawking effect and environmental noise (AD channels) on $�l_1$-norm of quantum coherence, FOC, CF and GC is studied. It is demonstrated that for systems with three physically accessible modes, the Hawking effect disrupts quantum coherence but exerts a positive influence on quantum entanglement under the AD channels. The remaining two scenarios exhibit the same behavior as the previous conclusions.