Quasiparticle dynamics in Andreev quantum dots

HUGUES POTHIER; LEANDRO TOSI; MARCELO GOFFMAN; CRISTIAN URBINA

Espoo

Conferencia; Mesoscopic Transport and Quantum Coherence 2017; 2017

In contrast with a bulk superconductor, a single-channel phase-biased superconducting weak link hosts a discrete subgap quasiparticle state, called ?Andreev state?. As such, it can be seen as a sort of quantum dot in which zero, one or two quasiparticles can be trapped, not due to electrostatic barriers, but to the phase drop. This ?Andreev quantum dot? constitutes a very simple playground to explore the foundations of mesoscopic superconductivity.I will present experiments on Andreev quantum dots obtained at one-atom contacts between aluminum electrodes, in which we probe the dynamics of quasiparticles trapping and un-trapping.