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arXiv · 2303.06750

Collisionless dynamics in disordered superconductors

Maxim Dzero
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Abstract

I consider relaxation of the pairing amplitude in a disordered Bardeen-Cooper-Schrieffer (BCS) superconductor in the absence of the two-particle collisions. My main assumption is that nonmagnetic and magnetic disorder scattering rates are much smaller than the value of the superconducting pairing gap $\Delta_0$. I derive a system of nonlinear equations which describe the collisionless relaxation of the pairing amplitude following a quench of the pairing strength. I find that in a superconductor in which scattering on paramagnetic impurities is dominant, the pairing amplitude in a steady state varies periodically with time even for small deviations from equilibrium. It is shown that such a steady state emerges due to scattering on paramagnetic impurities which leads to a decrease in the value of the resonant frequency of the amplitude mode below $2\Delta_0$.

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Maxim Dzero. 2023-03-12. Collisionless dynamics in disordered superconductors. https://doi.org/10.1103/physrevb.109.l100503

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