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DOE OSTI · 1774567

Nondispersing Wave Packets in Lattice Floquet Systems

Huang, Zhoushen·Clerk, Aashish·Martin, Ivar
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Abstract

We show that in a one-dimensional translationally invariant tight binding chain, nondispersing wave packets can in general be realized as Floquet eigenstates—or linear combinations thereof—using a spatially inhomogeneous drive, which can be as simple as modulation on a single site. The recurrence time of these wave packets (their “round-trip” time) locks in at rational ratios sT/r of the driving period T, where s, r are coprime integers. Wave packets of different s / r can coexist under the same drive, yet travel at different speeds. They retain their spatial compactness either infinitely (s/r = 1) or over a long time (s/r ≠ 1). Discrete time translation symmetry is manifestly broken for s ≠ 1, reminiscent of integer and fractional Floquet time crystals. We further demonstrate how to reverse engineer a drive protocol to reproduce a target Floquet micromotion, such as the free propagation of a wave packet, as if coming from a strictly linear energy spectrum. The variety of control schemes open up a new avenue for Floquet engineering in quantum information sciences.

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Huang, Zhoushen, Clerk, Aashish, Martin, Ivar. 2021-03-08. Nondispersing Wave Packets in Lattice Floquet Systems. https://doi.org/10.1103/physrevlett.126.100601

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