Transient transport spectroscopy of an interacting quantum dot proximized by a superconductor: Charge- and heat-currents after a switch

Abstract

We analyze the time-evolution of a quantum dot which is proximized by a large-gap superconductor and weakly probed using the charge and heat currents into a wide-band metal electrode. We map out the full time dependence of these currents after initializing the system by a switch. We find that due to the proximity effect there are two simple yet distinct switching procedures which initialize a non-stationary mixture of the gate-voltage dependent eigenstates of the proximized quantum dot. We find in particular that the ensuing time-dependent heat current is a sensitive two-particle probe of the interplay of strong Coulomb interaction and induced superconducting pairing. The pairing can lead to a suppression of charge and heat current decay which we analyze in detail. The analysis of the results makes crucial use of analytic formulas obtained using fermionic duality, a ``dissipative symmetry'' of the master equation describing this class of open systems.