Generating surface states in a Weyl semi-metal by applying electromagnetic radiation

Abstract

We show that the application of circularly polarized electromagnetic radiation on the surface of a Weyl semi-metal can generate states at that surface. These states can be characterized by their surface momentum. The Floquet eigenvalues of these states come in complex conjugate pairs rather than being equal to $\pm 1$. If the amplitude of the radiation is small, we find some unusual bulk-boundary relations: the Floquet eigenvalues of the surface states lie at the extrema of the Floquet eigenvalues of the bulk system, and the peaks of the Fourier transforms of the surface state wave functions lie at the momenta where the bulk Floquet eigenvalues have extrema. For the case of zero surface momentum, we can analytically derive scaling relations between the decay length of the surface states and the amplitude and penetration length of the radiation. For topological insulators, we again find that circularly polarized radiation can generate states on the surfaces; these states have much larger decay lengths than the surface states which are present even in the absence of radiation. Finally, we show that radiation can generate surface states for trivial insulators also.

14 pages, 10 figures; added a discussion and figure about density of Floquet eigenstates; this is the published version

References in corpus (10)

• Topological characterization of periodically-driven quantum systems
• Topological response in Weyl semimetals and the chiral anomaly
• Weyl Semimetals, Fermi Arcs and Chiral Anomalies (A Short Review)
• Irradiated graphene as a tunable Floquet topological insulator
• Photoinduced transition between conventional and topological insulators in two-dimensional electronic systems
• Negative longitudinal magnetoresistance in Dirac and Weyl metals
• Modulated Floquet Topological Insulators
• Friedel oscillations due to Fermi arcs in Weyl semimetals
• Theory of photoinduced Floquet Weyl semimetal phases
• Floquet dynamics in two-dimensional semi-Dirac semimetals and three-dimensional Dirac semimetals

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• A New Era of Quantum Materials Mastery and Quantum Simulators In and Out of Equilibrium