Josephson quantum mechanics at odd parity

Manuel Houzet; Julia S. Meyer; Yuli V. Nazarov

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arXiv · 2309.02728

Josephson quantum mechanics at odd parity

Manuel Houzet·Julia S. Meyer·Yuli V. Nazarov

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Abstract

A Josephson junction may be in a stable odd parity state when a single quasiparticle is trapped in an Andreev bound state. Embedding such junction in an electromagnetic environment gives rise to a special quantum mechanics of superconducting phase that we investigate theoretically. Our analysis covers several representative cases, from the lifting of the supercurrent quench due to quasiparticle poisoning for a low ohmic impedance of the environment, to a Schmid transition in a current-biased junction that for odd parity occurs at four times bigger critical impedance. For intermediate impedances, the supercurrent in the odd state is higher than in the even one.

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Manuel Houzet, Julia S. Meyer, Yuli V. Nazarov. 2023-09-06. Josephson quantum mechanics at odd parity. https://arxiv.org/abs/2309.02728

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