Die DPG-Frühjahrstagung in Hannover musste abgesagt werden! Lesen Sie mehr ...
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
Q: Fachverband Quantenoptik und Photonik
Q 13: Posters: Quantum Optics and Photonics I
Q 13.3: Poster
Montag, 9. März 2020, 16:30–18:30, Empore Lichthof
Weakly interacting Bose-Einstein condensates as quantum baths: (Pre)thermalization and nonequilibrium steady states — •Alexander Schnell and André Eckardt — Max-Planck-Institut für Physik komplexer Systeme, Dresden, Germany
Motivated by recent experimental progress [Phys. Rev. Lett. 121, 130403 (2018)], we study the dynamics of an ideal gas of bosonic impurity atoms which are weakly coupled to a weakly interacting background BEC. Using the standard open-quantum systems framework of Born-, Markov-, and rotating-wave approximation, we find a description of the impurity dynamics in terms of a Pauli rate equation. The rates have the typical structure of thermal rates for a (sub)ohmic bath with an additional factor that guarantees momentum conservation. For a free impurity atom with higher mass than the background atoms it was found [Phys. Rev. A 97, 023621 (2018)] that, due to momentum conservation, thermalization occurs only above a critical momentum. We find similar results for one or many impurity atoms that are additionally subjected to an optical lattice. We show that interesting nonequilibrium steady states can be engineered if the optical lattice is time-periodically driven.