Quasiparticle dynamics in Andreev quantum dots

LEANDRO TOSI; MARCELO GOFFMAN; HUGUES POTHIER; CRISTIAN URBINA

New HEaven

Workshop; Majorana Fermions and Beyond; 2017

Yale University

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 using circuit-QED like techniques [1]. I will focus in particular on the effect of the cavity on this dynamics.References[1] C. Janvier et al., Science 349, 1199 (2015)