Year: 2014
Type: article
Abstract: 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.
Source: Physical Review X
Authors: Ulrich Ebling, Jasper Simon Krauser, Nick Fläschner, Klaus Sengstock, Christoph Becker, Maciej Lewenstein, André Eckardt
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,200
Awards: G213344254, G3477530903
OpenAlex ID: W2014223423