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arXiv · 1503.05731

Nonlinear optical conductivity of $U(1)$ spin liquids with large spinon Fermi surfaces

Yuan-Fei Ma·Tai-Kai Ng
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Abstract

In this paper we study the nonlinear current response of $U(1)$ spin liquids with large spinon Fermi surfaces under the perturbation of a time-dependent ac electric field $\mathbf{E}(t)$ within the framework of an effective $U(1)$ gauge theory. In particular, the third-order nonlinear current response to ac electric fields is derived. We show that as in the case of linear current response, an in-gap power-law ($\simω^η$) response is found for the nonlinear current at low frequency. The nonlinear susceptibility may also induce through process of third harmonic generation propagating EM wave with frequency $3ω$ inside the spin liquids.

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Yuan-Fei Ma, Tai-Kai Ng. 2015-03-19. Nonlinear optical conductivity of $U(1)$ spin liquids with large spinon Fermi surfaces. https://doi.org/10.1103/physrevb.93.245109

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