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Accueil > Evénements > Séminaires > Archives 2016 > Condensation d’excitons
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Séminaire des doctorants de l’INSP

Condensation d’excitons noirs dans un piège - Romain Anankine - Jeudi 30 juin 2016 à 18 h

Romain Anankine - doctorant dans l’équipe Nanostructures et systèmes quantiques

INSP - 4 place Jussieu - 75252 PARIS Cedex 05 - Barre 22-32 - 2e étage, salle 201

Abstract

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Bosons, i.e. particles with an integer spin, can experiment a phase transition from a classical gas to a quantum degenerate one when we cool down the system and/or increase the density of particles. Predicted in 1924 (Bose & Einstein), this state of matter was first experimentally observed with alkaly atoms of Rubidium only in 1995 because of extremely low temperature ( 100 nK) needed to enter in the quantum regime. However, for decades, research on Bose-Einstein condensation also focused on bosonic semiconductor quasi-particles : electronic excitations, or excitons, are electron-hole pairs bound by Coulomb attraction and have the advantage to have a higher critical temperature accessible by cryogenic methods. Nevertheless, no unambiguous evidences were demonstrated because of the four-component spin structure where the ground state is a dark state, i.e. not coupled to light. In this seminar, I plan to show you the latest results of our lab group for the demonstration of the dark condensation and superfluidity of a trapped gas of excitons. These results pave the way for a rich many-body physics with tunable interactions between particles.