QSE Quantum Seminar: "Inelastic tunneling in a high impedance multimode microwave environment", Jérôme Esteve

Please join us for the QSE Center Quantum Seminar with Jérôme Esteve from the Université Paris-Saclay who will give the talk "Inelastic tunneling in a high impedance multimode microwave environment" on Thursday September 11th from 12pm to 1:30pm 
Location: BC 01

Pizzas will be available between the seminars at 12:00. All PhDs, postdocs, students, group leaders, and PIs are welcome to join us.

TITLE: "Inelastic tunneling in a high impedance multimode microwave environment"

ABSTRACT:
Bosonic degrees of freedom, such as vibrational or electromagnetic modes, can significantly influence the dc transport properties of mesoscopic conductors to which they are coupled. Depending on the microscopic processes involved, the conductance may be suppressed—for example, in dynamical Coulomb blockade—or enhanced through inelastic processes associated with bosonic excitations. These mechanisms are well established in the perturbative, weak-coupling regime, where the bosonic environment can be regarded as remaining close to thermal equilibrium. By contrast, in the strong-coupling regime, the non-equilibrium dynamics of the bosonic modes must be taken into account, and qualitatively new physics emerges. We investigate this regime in a tunnel junction coupled to the dense spectrum of microwave modes in a high-inductance superconducting transmission line. Our results demonstrate a pronounced renormalization of the conductance and uncover rich quantum-optical dynamics of the microwave environment, highlighting the interplay between strong electron–boson coupling and non-equilibrium many-body effects.

BIO: 
Jérôme Esteve is a researcher at the Laboratoire de Physique des Solides (LPS) in Orsay, France. His career has been dedicated to experimental quantum physics, with contributions spanning ultracold atoms, quantum optics, and cavity quantum electrodynamics (QED) during his time at the Laboratoire Kastler Brossel in Paris. He later joined the NS2 team at LPS, where his research focuses on microwave quantum optics in circuit QED and the study of unconventional superconductors.