Dynamics of Superconducting Correlations Induced by Hopping in Serial Double Quantum Dot System

Abstract

We study the quench dynamics of superconducting pairing correlations in the double quantum dot system coupled to superconducting and normal metallic electrodes. The quantum dots are initially isolated from each other, and the subsequent dynamics are induced by the sudden switching on hopping between them. We focus on the time-dependence of the real and imaginary parts of dots pairing potential and the role of the hopping amplitude and on-site Coulomb correlations. For relatively small hopping values, the evolution of the pairing potential is suppressed due to a strong single-occupation blockade. As the hopping amplitude increases, the pairing potential is dynamically redistributed between the dots and can eventually assume values of opposite signs. This effect is enhanced by the presence of strong on-site Coulomb interactions. The discussed numerical results are obtained by means of the time-dependent numerical renormalization group approach.