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arXiv · 2010.03879

Floquet higher order topological insulator in a periodically driven bipartite lattice

Weiwei Zhu·Y. D. Chong·Jiangbin Gong
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Abstract

Floquet higher order topological insulators (FHOTIs) are a novel topological phase that can occur in periodically driven lattices. An appropriate experimental platform to realize FHOTIs has not yet been identified. We introduce a periodically-driven bipartite (two-band) system that hosts FHOTI phases, and predict that this lattice can be realized in experimentally-realistic optical waveguide arrays, similar to those previously used to study anomalous Floquet insulators. The model exhibits interesting phase transitions from first-order to second-order topological matter by tuning a coupling strength parameter, without breaking lattice symmetry. In the FHOTI phase, the lattice hosts corner modes at eigenphase $0$ or $\pi$, which are robust against disorder in the individual couplings.

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Weiwei Zhu, Y. D. Chong, Jiangbin Gong. 2020-10-08. Floquet higher order topological insulator in a periodically driven bipartite lattice. https://doi.org/10.1103/physrevb.103.l041402

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