Séminaire de l'INPHYNI: Christian Miniatura (Inphyni)

In this seminar, intended as a pedagogical illustration of my research activity, I will focus, at a very general level, on an emblematic theoretical tool that I have been using since 2017 to study quantum transport: the Random Quantum Kicked Rotor. After outlining my areas of interest, I will introduce the classical kicked rotor, which has a long history in classical chaos studies. In particular, I'll show how repeated kicking induces a spatial diffusion in momentum space. Next, I will present the quantum kicked rotor (and its random offspring) and the coherent dynamic localization phenomenon that stops diffusion by destructive interference. I'll show that this localization phenomenon, which is similar to Anderson localization in real space, induces two interference peaks in position space on a diffusive background, the coherent backscattering (CBS) and coherent forward scattering (CFS) peaks. I'll show how these peaks encode the symmetry properties of the kicked system. Time permitting, I will briefly discuss interaction effects and the associated phenomena of pre-thermalization and condensation of classical waves.