arXiv:1910.12275 · Physical review. B./Physical review. B

Stochastic thermodynamics of an electron spin resonance quantum dot system

JunYan Luo, Yiying Yan, Hailong Wang, Jing Hu, Xiao-Ling He, Gernot Schaller

Published Mar 10, 2020• 8 citations

Abstract

We present a stochastic thermodynamics analysis of an electron spin resonance pumped quantum dot device in the Coulomb-blocked regime, where a pure spin current is generated without an accompanying net charge current. Based on a generalized quantum master equation beyond secular approximation, quantum coherences are accounted for in terms of an average spin in the Floquet basis. Elegantly, this average spin undergoes a precession about an effective magnetic field, which originates from the nonsecular treatment and energy renormalization. It is shown that the interaction between average spin and effective magnetic field may have the dominant roles to play in both energy transport and irreversible entropy production. In the stationary limit, the energy and entropy balance relations are also established based on the theory of counting statistics.

DOI: 10.1103/physrevb.101.125410

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