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arXiv · 1510.02185

Scaling laws for nonlinear electromagnetic responses of Dirac fermions

Takahiro Morimoto·Naoto Nagaosa
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Abstract

We theoretically propose that the Dirac fermion in two-dimensions shows the giant nonlinear responses to electromagnetic fields in terahertz region. A scaling form is obtained for the current and magnetization as functions of the normalized electromagnetic fields $E/E_ω$ and $B/B_ω$, where the characteristic electric (magnetic) field $E_ω$ ($B_ω$) depends on the frequency $ω$ as $\hbarω^2/ev_F$ ($\hbarω^2/ev_F^2$), and is typically of the order of 80 V/cm ( 8 mT) in the terahertz region. Applications of the present theory to graphene and surface state of a topological insulator are discussed.

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Takahiro Morimoto, Naoto Nagaosa. 2016-03-22. Scaling laws for nonlinear electromagnetic responses of Dirac fermions. https://doi.org/10.1103/physrevb.93.125125

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