Seminar on Disorder and strong electron correlations: "Universal physics in quantum nonequilibrium processes: Quantum quenches, work statistics and edge singularities"
Starts 1 Oct 2009 12:00
Ends 1 Oct 2009 20:00
Central European Time
Leonardo da Vinci Building Seminar Room
Strada Costiera, 11
I - 34151 Trieste (Italy)
A quantum quench is a rapid change in time of a control parameter in the Hamiltonian describing a quantum, correlated many-body system. The physics of this paradigmatic non-equilibrium process, which has been realized recently in the context of cold atoms, is of particular interest in quantum critical systems where concrete dynamical manifestations of universality can be studied. In this talk I will discuss two fundamental ways to characterize these processes, by either looking at the statistics of basic thermodynamic variables or at the asymptotics of correlators. I will first elucidate the connection between a classic problem in condensed matter physics, the Fermi edge singularity, the statistics of the work done in a quantum quench, and quantum Jarzynski equalities. Using this connection, I will discuss results for the statistics of the work in a variety of systems, such as the quantum Ising chain, the Dicke model and quantum impurities. I will show that quantum criticality manifests itself in the emergence of interesting edge singularities in the statistics of the work and discuss their universality. Similarly, I will discuss how the critical properties are encoded in the asymptotics of non-equilibrium correlators.