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arXiv · 1310.8043

Heat transport as torsional responses and Keldysh formalism in a curved spacetime

Atsuo Shitade
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Abstract

We revisit a theory of heat transport in the light of a gauge theory of gravity and find the proper heat current with a corresponding gauge field, which yields the natural definitions of the heat magnetization and the Kubo-formula contribution to the thermal conductivity as torsional responses. We also develop a general framework for calculating gravitational responses by combining the Keldysh and Cartan formalisms. By using this framework, we explicitly calculate these two quantities and reproduce the Wiedemann-Franz law for the thermal Hall conductivity in the clean and non-interacting case. Finally, we discuss an effective action for the quantized thermal Hall effect in $(2 + 1)$-D topological superconductors.

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Atsuo Shitade. 2013-10-30. Heat transport as torsional responses and Keldysh formalism in a curved spacetime. https://doi.org/10.1093/ptep/ptu162

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