2025/01/21 by Xiang Ji, Ji, Xiang, Hao Geng +5 · 2 citations
Physics and Astronomy · #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Quantum Physics (quant-ph) #Superconductivity (cond-mat.supr-con) #Superconductivity in MgB2 and Alloys #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2501.12129
openalex publication_date 2025/01/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
Non-Hermitian systems exhibit two distinct topological classifications based on their gap structure: line-gap and point-gap topologies. Although point-gap topology is intrinsic to non-Hermitian systems, its systematic construction remains a challenge. Here, we present the Floquet engineering approach for realizing point-gapped topological superconductors. By combining Floquet theory with particle-hole symmetry (PHS), we show that a point gap hosting robust Majorana edge modes emerges at the overlap of Floquet bands with opposite winding numbers. In the thermodynamic limit, even weak non-Hermiticity opens a point gap from a gapless spectrum, driving a topological phase transition and breaking non-Bloch parity-time (PT) symmetry. This transition is accompanied by the appearance of the Floquet Z2 skin effect. Furthermore, the point-gapped topological phase and the non-Bloch PT symmetry exhibit size-dependent phenomena driven by the critical skin effect. Our work offers a new pathway for exploring the point-gapped topological phases in non-Hermitian systems.