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DOE OSTI · 2338086

Floquet Insulators and Lattice Fermions

Iadecola, Thomas·Sen, Srimoyee·Sivertsen, Lars
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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. Finally, 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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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Iadecola, Thomas, Sen, Srimoyee, Sivertsen, Lars. 2024-03-26. Floquet Insulators and Lattice Fermions. https://doi.org/10.1103/physrevlett.132.136601

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