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arXiv · 1703.05525

Thermoelectric Transport through SU(N) Kondo Impurity

D. B. Karki·M. N. Kiselev
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Abstract

We investigate thermoelectric transport through a SU(N) quantum impurity in the Kondo regime. The strong coupling fixed point theory is described by the local Fermi-liquid paradigm. Using Keldysh technique we analyse the electric current through the quantum impurity at both finite bias voltage and finite temperature drop across it. The theory of a steady state at zero-current provides a complete description of the Seebeck effect. We find pronounced non-linear effects in temperature drop at low temperatures. We illustrate the significance of the non-linearities for enhancement of thermopower by two examples of SU(4) symmetric regimes characterized by a filling factor m: i) particle-hole symmetric at m=2 and ii) particle-hole non-symmetric at m=1. We analyse the effects of potential scattering and coupling asymmetry on the transport coefficients. We discuss connections between the theory and transport experiments with coupled quantum dots and carbon nanotubes.

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D. B. Karki, M. N. Kiselev. 2017-11-04. Thermoelectric Transport through SU(N) Kondo Impurity. https://doi.org/10.1103/physrevb.96.121403

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