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arXiv · 1708.01620

Exponentially Slow Heating in Short and Long-range Interacting Floquet Systems

Francisco Machado·Gregory D. Meyer·Dominic V. Else·Chetan Nayak·Norman Y. Yao
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Abstract

We analyze the dynamics of periodically-driven (Floquet) Hamiltonians with short- and long-range interactions, finding clear evidence for a thermalization time, $\tau^*$, that increases exponentially with the drive frequency. We observe this behavior, both in systems with short-ranged interactions, where our results are consistent with rigorous bounds, and in systems with long-range interactions, where such bounds do not exist at present. Using a combination of heating and entanglement dynamics, we explicitly extract the effective energy scale controlling the rate of thermalization. Finally, we demonstrate that for times shorter than $\tau^*$, the dynamics of the system is well-approximated by evolution under a time-independent Hamiltonian $D_{\mathrm{eff}}$, for both short- and long-range interacting systems.

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Francisco Machado, Gregory D. Meyer, Dominic V. Else, Chetan Nayak, Norman Y. Yao. 2017-08-04. Exponentially Slow Heating in Short and Long-range Interacting Floquet Systems. https://doi.org/10.1103/physrevresearch.1.033202

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