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arXiv · 2404.05485

Many-body quantum dynamics of spin-orbit coupled Andreev states in a Zeeman field

Kateryna Zatsarynna·Andrea Nava·Alex Zazunov·Reinhold Egger
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Abstract

We provide a theoretical framework to describe the quantum many-body dynamics of Andreev states in Josephson junctions with spin-orbit coupling and a magnetic Zeeman field. In such cases, employing a doubled Nambu spinor description is technically advantageous but one then has to be careful to avoid double-counting problems. By deriving the Lindblad master equation in the socalled excitation picture, we show that a physically consistent many-body theory free from doublecounting problems follows. We apply our formalism to a study of dynamical parity stabilization of the Andreev sector at intermediate times after an initial microwave pulse, in particular addressing the combined effects of spin-orbit coupling and Zeeman field.

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Kateryna Zatsarynna, Andrea Nava, Alex Zazunov, Reinhold Egger. 2024-04-08. Many-body quantum dynamics of spin-orbit coupled Andreev states in a Zeeman field. https://doi.org/10.1103/physrevb.109.214505

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