Floquet-Weyl and Floquet-topological-insulator phases in a stacked two-dimensional ring-network lattice

Tetsuyuki Ochiai

doi:10.1088/0953-8984/28/42/425501

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arXiv · 1604.08368

Floquet-Weyl and Floquet-topological-insulator phases in a stacked two-dimensional ring-network lattice

Tetsuyuki Ochiai

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Abstract

We show the presence of Floquet-Weyl and Floquet-topological-insulator phases in a stacked two-dimensional ring-network lattice. The Weyl points in the three-dimensional Brillouin zone and Fermi-arc surface states are clearly demonstrated in the quasienergy spectrum of the system in the Weyl phase. In addition, chiral surface states coexist in this phase. The Floquet-topological-insulator phase is characterized by the winding number of two in the reflection matrices of the semi-infinite system and resulting two gapless surface states in the quasienergy g ap of the bulk. The phase diagram of the system is derived in the two-parameter space of hopping S-matrices among the rings. We also discuss a possible optical realization of the system together with the introduction of synthetic gauge fields.

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Tetsuyuki Ochiai. 2016-04-28. Floquet-Weyl and Floquet-topological-insulator phases in a stacked two-dimensional ring-network lattice. https://doi.org/10.1088/0953-8984/28/42/425501

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