2023/10/26 by Zhihai Liu, Liu, Zhi-Hai, Wenkai Lou +5
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Graphene research and applications #Magnetic properties of thin films #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2310.17243
openalex publication_date 2023/10/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Narrow bandgap semiconductor nanostructures have been explored for realization of topological superconducting quantum devices in which Majorana states can be created and employed for constructing topological qubits. However, a prerequisite to achieve the topological phase transition in these nanostructures is application of a magnetic field, which could complicate the technology development towards topological quantum computing. Here we demonstrate that a topological phase transition can be achieved in a narrow bandgap semiconductor nanolayer under application of a perpendicular electric field. Based on full band structure calculations, it is shown that the topological phase transition occurs at an electric-field induced band inversion and is accompanied by a sharp change of the ℤ2 invariant at the critical field. We also demonstrate that the nontrivial topological phase is manifested by the quantum spin Hall edge states in a band-inverted nanolayer Hall-bar structure. We present the phase diagram of the nanolayer in the space of layer thickness and electric field strength, and discuss the optimal conditions to achieve a large topological bandgap in the electric-field induced topological phase of a semiconductor nanolayer.