Dynamics of quasiparticles in Andreev quantum dots

HUGUES POTHIER; LEANDRO TOSI; MARCELO GOFFMAN; CRISTIAN URBINA

Gothenburg

Conferencia; LT 28 Gothenburg; 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 quasiparticles can be trapped, not due to electrostatic barriers, but to the phase drop. I will present vey recent experiments in which, by coupling Andreev quantum dots obtained at one-atom contacts between aluminum electrodes to a microwave resonator (circuit-QED setup) [1], we probe the transitions between states with 0, 1 and 2 quasiparticles.