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arXiv · 2307.06589

Dynamical freezing and switching in periodically driven bilayer graphene

Soumya Sasidharan·Naveen Surendran
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Abstract

A class of integrable models, such as the one-dimensional transverse-field Ising model, respond nonmonotonically to a periodic drive with respect to the driving parameters and freezes almost absolutely for certain combinations of the latter. In this paper, we go beyond the two-band structure of the Ising-like models studied previously and ask whether such unusual nonmonotonic response and near-absolute freezing occur in integrable systems with a higher number of bands. To this end, we consider a tight-binding model for bilayer graphene subjected to an interlayer potential difference. We find that when the potential is driven periodically, the system responds nonmonotonically to variations in the driving amplitude $V_0$ and frequency $ω$ and shows near absolute freezing for certain values of $V_0/ω$. However, the freezing occurs only in the presence of a constant bias in the driving, i.e., when $V= V'+V_0 \cos{ωt}$. When $V'=0$, the freezing is switched off for all values of $V_0/ω$. We support our numerical results with analytical calculations based on a rotating wave approximation. We also give a proposal to realize the driven bilayer system via ultracold atoms in an optical lattice, where the driving can be implemented by shaking the lattice.

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Soumya Sasidharan, Naveen Surendran. 2023-07-13. Dynamical freezing and switching in periodically driven bilayer graphene. https://doi.org/10.1103/physrevb.107.174301

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