Quench dynamics of correlated quantum dot proximitized to superconducting lead

TL;DR

This paper studies the non-equilibrium dynamics of a correlated quantum dot connected to metallic and superconducting leads, focusing on how sudden changes affect charge, pairing, and quasiparticle states, with potential experimental observations.

Contribution

It introduces a detailed analysis of quench dynamics in a quantum dot with both electron correlations and superconducting proximity effects, highlighting new transient behaviors.

Findings

Time-dependent charge occupancy shows characteristic relaxation patterns.

Transient currents reveal signatures of quasiparticle evolution.

Subgap quasiparticle states evolve distinctly after quenches, observable in tunneling conductance.

Abstract

Quantum system abruptly driven from its stationary phase can reveal nontrivial dynamics upon approaching a new final state. We investigate here such dynamics for a correlated quantum dot sandwiched between the metallic and superconducting leads, considering two types of quenches feasible experimentally. In particular, we examine an interplay between the proximity induced electron pairing with correlations caused by the on-dot Coulomb repulsion. We discuss the time-dependent charge occupancy, complex order parameter, transient currents, and analyze evolution of the subgap quasiparticles which could be empirically observed in the tunneling conductance.