Seminar coming up next Thursday

[Cond.Matt. & Stat.Mech.Section]

SEMINAR on     Disorder and strong electron correlations

 

Thursday, 31 October -  11:30 a.m.

 
 

Luigi Stasi Seminar Room,  Leonardo Building - first floor

 



Thomas GASENZER   ( University of Heidelberg )

 


"Non-thermal fixed points:  Universality, topology and turbulence in  Bose systems"

 

Abstract

 

Among the wealth of possible non-equilibrium many-body configurations most interesting candidates are those which show universal behavior.  New, non-thermal fixed points are proposed, leading beyond standard equilibrium critical points.  A selection of phenomena in ultracold Bose gases, characterized by specific power-laws in space and time, and universal time evolution will be presented.  These are, for generic cases, related to the presence and turbulent dynamics of (quasi-)topological defects in the Bose field, which are manifestly far from equilibrium.  Examples how to reach these critical points which will be discussed include interaction quenches and rapid evaporative cooling.  Our results confirm non-perturbative quantum field theoretical predictions and establish a new link between kinetic wave turbulence and topological excitations of superfluids.  They open a path to explore a new class of universal far-from-equilibrium dynamics well accessible in ultracold gas experiments.  These phenomena are of importance far beyond the realm of cold gases and allow a view on new classifications of universal far-from-equilibrium physics.