2025/08/01 by Yiting Deng, Yan He, Deng, Yiting +1
Materials Science · Physics and Astronomy · #Chemical and Physical Properties of Materials #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum many-body systems #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2508.00277
openalex publication_date 2025/08/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the higher-order topological insulators at finite temperature based on a generalized real-space quadrupole moment, which extends the ground state expectations to ensemble averages. Our study reveals that chiral symmetry alone dictates that the quadrupole moment must be quantized to two values of 0 and 1/2, even at finite temperature. It is found that finite temperature can induce a topological phase transition from non-trivial to trivial. Furthermore, we found that the anisotropic intra-cell hopping can lead to a reentrant topological phase transition, in which the system becomes topological again with rising temperature. This reentrant behavior is in stark contrast to the results at zero temperature. We also investigate the effects of the quasi-disorder hopping on the topology. It is found that the initially trivial system can be driven into a topological phase with strong enough disorder strength, which closely resembles the topological Anderson transition. Our work provides an example for studying the finite temperature topology of higher-order topological insulators.