Relaxation Dynamics of an Isolated Large-Spin Fermi Gas Far from Equilibrium

A fundamental question in many-body physics is how closed quantum systems reach equilibrium. We address this question experimentally and theoretically in an ultracold large-spin Fermi gas where we find a complex interplay between internal and motional degrees of freedom. The fermions are initially p...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Ulrich Ebling, Jasper Simon Krauser, Nick Fläschner, Klaus Sengstock, Christoph Becker, Maciej Lewenstein, André Eckardt
Formato: article
Lenguaje:EN
Publicado: American Physical Society 2014
Materias:
Acceso en línea:https://doaj.org/article/60683d910a014871a086c6c99843c85e
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:A fundamental question in many-body physics is how closed quantum systems reach equilibrium. We address this question experimentally and theoretically in an ultracold large-spin Fermi gas where we find a complex interplay between internal and motional degrees of freedom. The fermions are initially prepared far from equilibrium with only a few spin states occupied. The subsequent dynamics leading to redistribution among all spin states is observed experimentally and simulated theoretically using a kinetic Boltzmann equation with full spin coherence. The latter is derived microscopically and provides good agreement with experimental data without any free parameters. We identify several collisional processes that occur on different time scales. By varying density and magnetic field, we control the relaxation dynamics and are able to continuously tune the character of a subset of spin states from an open to a closed system.