Quasiparticle dynamics in Andreev quantum dots

LEANDRO TOSI; MARCELO GOFFMAN; HUGUES POTHIER; CRISTIAN URBINA

Berlin

Conferencia; Spring Meeting of German Physical Society; 2018

DPG

In contrast with a bulk superconductor, a single-channel phase-biasedsuperconducting weak link hosts a discrete subgap quasiparticle state,called "Andreev state". It can be seen as a sort of quantum dot inwhich zero, one or two quasiparticles can be trapped, not due to electrostaticbarriers, but to the phase drop. This "Andreev quantumdot" constitutes a very simple playground to explore the foundationsof mesoscopic superconductivity.I will present experiments on Andreev quantum dots obtained atone-atom contacts between aluminum electrodes, in which we probethe dynamics of quasiparticles trapping and un-trapping using circuitQEDlike techniques [1]. I will focus in particular on the effect of thecavity on this dynamics.[1] C. Janvier et al., Science 349, 1199 (2015)