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Universal linear and nonlinear electrodynamics of a Dirac fluid.

ABSTRACT: A general relation is derived between the linear and second-order nonlinear ac conductivities of an electron system in the hydrodynamic regime of frequencies below the interparticle scattering rate. The magnitude and tensorial structure of the hydrodynamic nonlinear conductivity are shown to differ from their counterparts in the more familiar kinetic regime of higher frequencies. Due to universality of the hydrodynamic equations, the obtained formulas are valid for systems with an arbitrary Dirac-like dispersion, ranging from solid-state electron gases to free-space plasmas, either massive or massless, at any temperature, chemical potential, or space dimension. Predictions for photon drag and second-harmonic generation in graphene are presented as one application of this theory.

SUBMITTER: Sun Z

PROVIDER: S-EPMC5879671 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Universal linear and nonlinear electrodynamics of a Dirac fluid.

Sun Zhiyuan Z Basov Dmitry N DN Fogler Michael M MM

Proceedings of the National Academy of Sciences of the United States of America 20180312 13

A general relation is derived between the linear and second-order nonlinear ac conductivities of an electron system in the hydrodynamic regime of frequencies below the interparticle scattering rate. The magnitude and tensorial structure of the hydrodynamic nonlinear conductivity are shown to differ from their counterparts in the more familiar kinetic regime of higher frequencies. Due to universality of the hydrodynamic equations, the obtained formulas are valid for systems with an arbitrary Dira ...[more]

PMID: 29531071

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