Abstract
Floquet engineering has attracted considerable attention as a promising approach for tuning topological phase transitions.We investigate the effects of high-frequency time-periodic driving in a four-dimensional(4D)topological insulator,focusing on topological phase transitions at the off-resonant quasienergy gap.The 4D topological insulator hosts gapless three-dimensional boundary states,characterized by the second Chern number C2.We demonstrate that the second Chern number of 4D topological insulators can be modulated by tuning the amplitude of time-periodic driving.This includes transitions from a topological phase with C2=±3 to another topological phase with C2=±1,or to a topological phase with an even second Chern number C2=±2,which is absent in the 4D static system.Finally,the approximation theory in the high-frequency limit further confirms the numerical conclusions.
基金项目
国家自然科学基金(12074107)
国家自然科学基金(12304195)
Program of Outstanding Young and Middle-Aged Scientific and Technological Innovation Team of Colleges and Universities in Hu(T2020001)
Innovation Group Project of the Natural Science Foundation of Hubei Province of China(2022CFA012)
Chutian Scholars Program in Hubei Province()
Postdoctoral Fellowship Program of CPSF(GZC20230751)
Postdoctoral Innovation Research Program in Hubei Province(351342)
维普
万方数据