ELFT HÍRADÓ

[Janos Asboth <asboth.janos AT wigner.mta.hu>]

*Wigner SZFI Quantum Optics and Quantum Information Seminar*
Thermalization time scales from entanglement dynamics

*Tibor Rakovszky*
Technical University, Munchen

Friday, 17 May 2019 13:00, KFKI Campus, Bldg. 1, 2nd floor, Conference Room

While it has been known for a while that quantum many-body systems obeying
the Eigenstate Thermalization Hypothesis reach thermal equilibrium at long
times, their rich physics before thermalization, and the variety of time
scales involved are still being explored. In my talk I will show how
signatures of these different time scales appear in the entanglement
spectrum of a local subsystem. In particular, I will discuss two phenomena.
I will show that the onset of level repulsion in the entanglement spectrum
of a finite subsystem can be used to extract the Lieb-Robinson velocity,
which characterizes how the information contained in an initially local
operator spreads in the system. On the other hand, I will argue that the
dynamics of the largest eigenvalues of the reduced density matrix are
strongly influenced by diffusive modes (stemming from conservation laws),
and consequently have much slower dynamics then typical eigenvalues. This
latter phenomenon is relevant for experimentally observable Rényi
entanglement entropies.

Reference:
T Rakovszky, S Gopalakrishnan, S. A. Parameswaran, F Pollmann,
arXiv:1901.04444

Everyone is welcome to attend.

János Asbóth