title: Relaxation and prethermalization in an isolated quantum system.
abstract: Understanding relaxation processes is an important unsolved problem in many areas of physics. A key challenge is the scarcity of experimental tools for the characterization of complex transient states. We used measurements of full quantum mechanical probability distributions of matter-wave interference to study the relaxation dynamics of a coherently split one-dimensional Bose gas and obtained comprehensive information about the dynamical states of the system. After an initial rapid evolution, the full distributions reveal the approach toward a thermal-like steady state characterized by an effective temperature that is independent from the initial equilibrium temperature of the system before the splitting process. We conjecture that this state can be described through a generalized Gibbs ensemble and associate it with prethermalization.
authors.affiliation: Vienna Center for Quantum Science and Technology, Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Vienna, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Gring
authors.forename: M
authors.initials: M
authors.lastname: Kuhnert
authors.forename: T
authors.initials: T
authors.lastname: Langen
authors.forename: T
authors.initials: T
authors.lastname: Kitagawa
authors.forename: B
authors.initials: B
authors.lastname: Rauer
authors.forename: M
authors.initials: M
authors.lastname: Schreitl
authors.forename: I
authors.initials: I
authors.lastname: Mazets
authors.forename: D Adu
authors.initials: DA
authors.lastname: Smith
authors.forename: E
authors.initials: E
authors.lastname: Demler
authors.forename: J
authors.initials: J
authors.lastname: Schmiedmayer