Seminar on Friday

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

JOINT ICTP/SISSA STATISTICAL PHYSICS SEMINAR



Friday, 10 April   -   11:00 a.m.

 

 SISSA, Santorio Building,   Room 005 (Ground floor)

 

 Maurizio FAGOTTI    (Paris)

 

 

" Impact of hidden symmetry breaking on the non-equilibrium time evolution of  local observables and entanglement entropies "



Abstract

I discuss some effects of (interacting) perturbations to the Hamiltonian of the quantum XY model in the non-equilibrium time evolution after a global quench. At sufficiently large times the perturbations dramatically affect the expectation values of local observables. The leading contribution can be traced back to the breaking of non-abelian integrability, which is manifest at times proportional to the inverse perturbation strength. I describe different scenarios for the time evolution of observables, focusing on the emergence of persistent oscillations. Finally, I point out a scaling behaviour for the time evolution of the entanglement entropies of spin blocks, which is essentially independent of the quench details.