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arXiv · 2208.03544

Floquet topological phase transitions in a periodically quenched dimer

Milad Jangjan·Luis E. F. Foa Torres·Mir Vahid Hosseini
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Abstract

We report on the theoretical investigation of the topological properties of a periodically quenched one-dimensional dimerized lattice where a piece-wise constant Hamiltonian switches from $h_1$ to $h_2$ at a partition time $t_p$ within each driving period $T$. We examine different dimerization patterns for $h_1$ and $h_2$ and the interplay with the driving parameters that lead to the emergence of topological states both at zero energy and at the edge of the Brillouin-Floquet quasi-energy zone. We illustrate different phenomena, including the occurrence of both edge states in a semimetal spectrum, the topological transitions, and the generation of zero-energy topological states from trivial snapshots. The role of the different symmetries in our results is also discussed.

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Milad Jangjan, Luis E. F. Foa Torres, Mir Vahid Hosseini. 2022-08-06. Floquet topological phase transitions in a periodically quenched dimer. https://doi.org/10.1103/physrevb.106.224306

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