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arXiv · 2110.10100

Pair-amplitude dynamics in strongly-coupled superconductor-quantum dot hybrids

Markus Heckschen·Björn Sothmann
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Abstract

We consider a three-terminal system consisting of a quantum dot strongly coupled to two superconducting reservoirs in the infinite gap limit and weakly coupled to a normal metal. Using a real-time diagrammatic approach, we calculate the dynamics of the proximity-induced pair amplitude on the quantum dot. We find that after a quench the pair amplitude shows pronounced oscillations with a frequency determined by the coupling to the superconductors. In addition, it decays exponentially on a time scale set by the coupling to the normal metal. Strong oscillations of the pair amplitude occur also when the system is periodically driven both in the adiabatic and fast-driving limit. We relate the dynamics of the pair amplitude to the Josephson and Andreev current through the dot to demonstrate that it is an experimentally accessible quantity.

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Markus Heckschen, Björn Sothmann. 2021-10-19. Pair-amplitude dynamics in strongly-coupled superconductor-quantum dot hybrids. https://doi.org/10.1103/physrevb.105.045420

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