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arXiv · 2306.16463

Floquet insulators and lattice fermions

Thomas Iadecola·Srimoyee Sen·Lars Sivertsen
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Abstract

Floquet insulators are periodically driven quantum systems that can host novel topological phases as a function of the drive parameters. These new phases exhibit features reminiscent of fermion doubling in discrete-time lattice fermion theories. We make this suggestion concrete by mapping the spectrum of a noninteracting (1+1)D Floquet insulator for certain drive parameters onto that of a discrete-time lattice fermion theory with a time-independent Hamiltonian. The resulting Hamiltonian is distinct from the Floquet Hamiltonian that generates stroboscopic dynamics. It can take the form of a discrete-time Su-Schrieffer-Heeger model with half the number of spatial sites of the original model, or of a (1+1)D Wilson-Dirac theory with one quarter of the spatial sites.

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Thomas Iadecola, Srimoyee Sen, Lars Sivertsen. 2023-06-28. Floquet insulators and lattice fermions. https://arxiv.org/abs/2306.16463

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