Scientific Calendar Event

Starts 21 Nov 2023 11:00
Ends 21 Nov 2023 12:00
Central European Time
SISSA (via Bonomea) room 128 + via Zoom

Shachar Fraenkel
(Tel Aviv University

Out-of-equilibrium states of many-body systems tend to evade a description by standard statistical mechanics, and their uniqueness is epitomized by the possibility of certain long-range correlations that cannot occur in equilibrium. In quantum many-body systems, coherent correlations of this sort may lead to the emergence of remarkable entanglement structures. In this talk, I will present exact analytical results concerning entanglement within the steady state of free fermions that occupy a one-dimensional lattice containing a noninteracting impurity, and that are subjected to an external bias by two edge reservoirs. I will show that two subsystems located on opposite sides of the impurity, and within a similar distance from it, exhibit volume-law entanglement regardless of their separation, as measured by their fermionic negativity. The mutual information of the subsystems, which quantifies the total (classical and quantum) correlations between them, follows a similar scaling. This behavior arises whenever the energy distribution functions of the two edge reservoirs differ, thus capturing both the case of a chemical-potential bias and the case of a temperature bias (as well as any combination of the two). The extensive terms of the negativity and mutual information feature a simple and universal functional dependence on the scattering probabilities associated with the impurity, a functional dependence which has a clear interpretation in terms of the coherence generated between the transmitted and reflected parts of scattered wavepackets. To the extent that time permits, I will discuss further exact results for the subleading corrections to these asymptotic expressions in the case of zero temperature.
Shachar Fraenkel and Moshe Goldstein, SciPost Phys. 15, 134 (2023)
Shachar Fraenkel and Moshe Goldstein, arXiv:2310.16901 (2023)
Shachar Fraenkel and Moshe Goldstein, arXiv:2312.XXXXX (in preparation)