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arXiv · 1704.08939

Optical absorption in interacting and nonlinear Weyl semimetals

Simon Bertrand·Ion Garate·René Côté
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Abstract

It has been recently predicted that the interplay between Coulomb interactions and Berry curvature can produce interesting optical phenomena in topologically nontrivial two-dimensional insulators. Here, we present a theory of the optical absorption for three-dimensional, hole-doped Weyl semimetals. We find that the Berry curvature, Coulomb interactions and the nonlinearity in the single-particle energy spectrum can together enable a light-induced valley polarization. We support and supplement our numerical results with an analytical toy model calculation, which unveils topologically nontrivial Mahan excitons with nonzero vorticity.

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Simon Bertrand, Ion Garate, René Côté. 2017-04-28. Optical absorption in interacting and nonlinear Weyl semimetals. https://doi.org/10.1103/physrevb.96.075126

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