ELFT HÍRADÓ

[tcsaba <tcsaba AT eik.bme.hu>]

                 M E G H Í V Ó - I N V I T A T I O N

    Seminar Series of the Department of Theoretical Physics at the
           Budapest University of Technology and Economics


                         Lorenzo Piroli
                            (SISSA)

           Transport in out-of-equilibrium XXZ chains
                from generalized hydrodynamics


The last year has witnessed a breakthrough in the study of transport in 
interacting integrable systems, with the introduction of the so-called 
generalized hydrodynamic approach. The latter allows us to give 
quantitative predictions for the long-time limit in non-homogeneous 
settings out of equilibrium. Among these, a popular protocol has been 
the one of quantum quenches from initially bipartite systems: two 
semi-infinite halves of a one-dimensional system, initially prepared in 
different macroscopic states, are suddenly joined together and then left 
to evolve unitarily with a given Hamiltonian. At large times, the system 
can be locally represented by a family of space- and time-dependent 
stationary states, which are fully characterized by a set hydrodynamic 
equations. After reviewing the general ideas, I will present further 
developments of the theory and several recent results. I will focus in 
particular on the prototypical case of the XXZ spin-1/2 chain and show 
how the generalized hydrodynamic equations can account for a rich 
phenomenology depending on the specific choice of the system's 
parameters. A detailed discussion of transport features will be 
presented, including the emergence of sub-ballistic behavior in the 
gapped phase and of interesting universal effects in the gapless regime. 
This talk is based on the following works:

L. Piroli, J. De Nardis, M. Collura, B. Bertini, and M. Fagotti, PRB 96, 
(2017)
B. Bertini and L. Piroli, arXiv:1711.00519 (2017)
B. Bertini, L. Piroli, and P. Calabrese, arXiv:1709.10096 (2017)


Időpont: 2017. december 15. péntek, 10:15
Helyszín: BME Fizikai Intézet, Elméleti Fizika Tanszék,
Budafoki út 8. F-épület, III lépcsőház, szemináriumi szoba