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arXiv · 1111.4518

Topological Floquet Spectrum in Three Dimensions via a Two-Photon Resonance

Netanel H. Lindner·Doron L. Bergman·Gil Refael·Victor Galitski
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Abstract

A recent theoretical work [Nature Phys., 7, 490 (2011)] has demonstrated that external non-equilibrium perturbations may be used to convert a two-dimensional semiconductor, initially in a topologically trivial state, into a Floquet topological insulator. Here, we develop a non-trivial extension of these ideas to three-dimensional systems. In this case, we show that a two-photon resonance may provide the necessary twist needed to transform an initially unremarkable band structure into a topological Floquet spectrum. We provide both an intuitive, geometrical, picture of this phenomenon and also support it by an exact solution of a realistic lattice model that upon irradiation features single topological Dirac modes at the two-dimensional boundary of the system. It is shown that the surface spectrum can be controlled by choosing the polarization and frequency of the driving electromagnetic field. Specific experimental realizations of a three-dimensional Floquet topological insulator are proposed.

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Netanel H. Lindner, Doron L. Bergman, Gil Refael, Victor Galitski. 2011-11-18. Topological Floquet Spectrum in Three Dimensions via a Two-Photon Resonance. https://doi.org/10.1103/physrevb.87.235131

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