Physikalisches Kolloquium: Prof. Dr. Francesco Piazza – Non-equilibrium as a resource: Non-thermal steady-states of cavity-quantum-materials

Titel: Non-equilibrium as a resource: Non-thermal steady-states of cavity-quantum-materials

Abstract:
Coupling a system to two different baths can lead to novel phenomena escaping the constraints of thermal equilibrium. In quantum materials inside optical cavities, this feature can be exploited as electrons and cavity-photons are easily pulled away from their mutual equilibrium, even in the steady state. This offers new routes for a non-invasive control of material properties and functionalities. Motivated by recent experimental puzzles arising with transition-metal-dichalcogenides inside Fabry-Perot cavities, we show how the absence of thermal equilibrium between electrons and photons leads to qualitative modifications of the material's properties in two different ways: 1) the electron distribution shows enhanced fluctuations near the Fermi surface due to the breaking of detailed balance; 2) the scattering between electrons in the steady state acquires a genuinely non-thermal component which can for instance enhance the tendency to pair and become superconducting.

Sprecher / Speaker: Prof. Dr. Francesco Piazza, Universität Augsburg
Kontakt / Contact: Prof. Dr. Daniele Fausti