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Hydrodynamic theory of thermoelectric transport and negative magnetoresistance in Weyl semimetals.

ABSTRACT: We present a theory of thermoelectric transport in weakly disordered Weyl semimetals where the electron-electron scattering time is faster than the electron-impurity scattering time. Our hydrodynamic theory consists of relativistic fluids at each Weyl node, coupled together by perturbatively small intervalley scattering, and long-range Coulomb interactions. The conductivity matrix of our theory is Onsager reciprocal and positive semidefinite. In addition to the usual axial anomaly, we account for the effects of a distinct, axial-gravitational anomaly expected to be present in Weyl semimetals. Negative thermal magnetoresistance is a sharp, experimentally accessible signature of this axial-gravitational anomaly, even beyond the hydrodynamic limit.

SUBMITTER: Lucas A

PROVIDER: S-EPMC5003291 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Hydrodynamic theory of thermoelectric transport and negative magnetoresistance in Weyl semimetals.

Lucas Andrew A Davison Richard A RA Sachdev Subir S

Proceedings of the National Academy of Sciences of the United States of America 20160810 34

We present a theory of thermoelectric transport in weakly disordered Weyl semimetals where the electron-electron scattering time is faster than the electron-impurity scattering time. Our hydrodynamic theory consists of relativistic fluids at each Weyl node, coupled together by perturbatively small intervalley scattering, and long-range Coulomb interactions. The conductivity matrix of our theory is Onsager reciprocal and positive semidefinite. In addition to the usual axial anomaly, we account fo ...[more]

PMID: 27512042

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