laboratoire pierre aigrain
électronique et photonique quantiques
 
laboratoire pierre aigrain
 

April 1, 2016 - 2pm - Salle Jaurès (29 rue d’Ulm)

Laure Bruhat
Microwaves as a probe of quantum dot circuits : from Kondo dynamics to mesoscopic quantum electrodynamics


The public thesis defense of Laure Bruhat will take place on April 1, 2016 at 2pm in Salle Jaurès (29 rue d’Ulm). She realized her PhD work under the supervision of Takis Kontos.

Abstract:

This thesis uses microwaves as probe of carbon nanotube quantum dot circuits. In a first experiment, a microwave excitation is directly applied to a circuit electrode for a quantum dot in the Kondo regime. We provide the first frequency-amplitude characterisation of the Kondo zero-bias conductance. Preliminary data are consistent with predicted universal behaviour. We present two other experiments, where quantum dot circuits are embedded in microwave resonators. Cavity photons probe charge relaxation resistance and photon-emission in a quantum dot coupled to normal and superconducting reservoirs in presence of Coulomb repulsion. Our observations validate a modelling in terms of the circuit linear response. We also present the first implementation of a Cooper pair splitter in cavity. The strong coupling regime is achieved, a premiere with quantum dot circuits. Our findings support the idea, that mesoscopic quantum electrodynamics is a fruitful toolbox in the context of both fields of quantum transport and quantum information science.