arXiv:2307.06589 · Physical review. B./Physical review. B
Dynamical freezing and switching in periodically driven bilayer graphene
Soumya Sasidharan, Naveen Surendran
Abstract
A class of integrable models, such as the one-dimensional transverse-field Ising model, responds 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 an 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 $\ensuremath{\omega}$ and shows near-absolute freezing for certain values of ${V}_{0}/\ensuremath{\omega}$. However, the freezing occurs only in the presence of a constant bias in the driving, i.e., when $V={V}^{\ensuremath{'}}+{V}_{0}cos\ensuremath{\omega}t$. When ${V}^{\ensuremath{'}}=0$, the freezing is switched off for all values of ${V}_{0}/\ensuremath{\omega}$. 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.