Tim Langen (Vienna):

Relaxation and Prethermalization in an Isolated Quantum System

Abstract:

Non-equilibrium quantum dynamics constitute a fundamental open problem in many fields of physics, ranging from the dynamics in the early universe and heavy-ion collisions [1] to the subtle coherence and transport properties in condensed matter systems. We use matter-wave interference to experimentally study the relaxation dynamics of a one-dimensional Bose gas following a quench [2]. This reveals the approach towards an intermediate thermal-like steady state, the properties of which are determined by the quantum fluctuations introduced during the quench. Our results constitute the first direct observation of prethermalization.

[1] J. Berges, S. Borsányi, C. Wetterich, Phys. Rev. Lett. 93, 142002 (2004)
[2] M. Gring et al., Science 337, 1318 (2012)