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arXiv · 2003.05638

Floquet and Anomalous Floquet Weyl Semimetals

Yufei Zhu·Tao Qin·Xinxin Yang·Gao Xianlong·Zhaoxin Liang
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Abstract

The periodic driving of a quantum system can enable new topological phases without analogs in static systems. This provides a route towards preparing non-equilibrium quantum phases rooted into the non-equilibrium nature by periodic driving engineering. Motivated by the ongoing considerable interest in topological semimetals, we are interested in the novel topological phases in the periodically driven topological semimetals without a static counterpart. We propose to design non-equilibrium topological semimetals in the regime of weakly driving field where the spectrum width of shares the same magnitude with the driving frequency. We identify two novel types of non-equilibrium Weyl semimetals (i.e., Floquet and anomalous Floquet Weyl semimetals) that do not exhibit analogues in equilibrium. The proposed setup is shown to be experimentally feasible using the state-of-the-art techniques used to control ultracold atoms in optical lattices.

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Yufei Zhu, Tao Qin, Xinxin Yang, Gao Xianlong, Zhaoxin Liang. 2020-03-12. Floquet and Anomalous Floquet Weyl Semimetals. https://doi.org/10.1103/physrevresearch.2.033045

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