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arXiv · 2108.05843

Floquet theory of photoinduced topological phase transitions in the organic salt $\alpha$-(BEDT-TTF)$_2$I$_3$ irradiated with elliptically polarized light

Keisuke Kitayama·Yasuhiro Tanaka·Masao Ogata·Masahito Mochizuki
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Abstract

We theoretically investigate possible photoinduced topological phase transitions in the organic salt $\alpha$-(BEDT-TTF)$_2$I$_3$, which possesses a pair of inclined massless Dirac-cone bands between the conduction and valence bands under uniaxial pressure. The Floquet analyses of a driven tight-binding model for this material reveal rich photoinduced variations of band structures, Chern numbers, and Hall conductivities under irradiation with elliptically polarized light. The obtained phase diagrams contain a variety of nonequilibrium steady phases, e.g., the Floquet Chern insulator, Floquet semimetal, and Floquet normal insulator phases. This work widens a scope of target materials for research on photoinduced topological phase transitions and contributes to development of research on the optical manipulations of electronic states in matters.

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Keisuke Kitayama, Yasuhiro Tanaka, Masao Ogata, Masahito Mochizuki. 2021-08-12. Floquet theory of photoinduced topological phase transitions in the organic salt $\alpha$-(BEDT-TTF)$_2$I$_3$ irradiated with elliptically polarized light. https://doi.org/10.7566/jpsj.90.104705

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