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arXiv · 1801.01683

Floquet Weyl semimetals in light-irradiated type-II and hybrid line-node semimetals

Rui Chen·Bin Zhou·Dong-Hui Xu
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Abstract

Type-II Weyl semimetals have recently attracted intensive research interest because they host Lorentz-violating massless fermions as quasiparticles. The discovery of type-II Weyl semimetals evokes the study of type-II line-node semimetals (LNSMs) whose linear dispersion is strongly tilted near the nodal ring. We present here a study on the circularly polarized light-induced Floquet states in type-II LNSMs, as well as those in hybrid LNSMs that have a partially over-tilted linear dispersion in the vicinity of the nodal ring. We illustrate that two distinct types of Floquet Weyl semimetal (WSM) states can be induced in periodically driven type-II and hybrid LNSMs, and the type of Floquet WSMs can be tuned by the direction and intensity of the incident light. We construct phase diagrams of light irradiated type-II and hybrid LNSMs which are quite distinct from those of light-irradiated type-I LNSMs. Moreover, we show that the photoinduced Floquet type-I and type-II WSMs can be characterized by the emergence of different anomalous Hall conductivities.

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Rui Chen, Bin Zhou, Dong-Hui Xu. 2019-07-02. Floquet Weyl semimetals in light-irradiated type-II and hybrid line-node semimetals. https://doi.org/10.1103/physrevb.97.155152

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