SP Seminar 15.04.16 @SISSA: Jean-Marie Stephan

[Condensed Matter Section]

JOINT ICTP/SISSA STATISTICAL PHYSICS SEMINAR

Friday 15 April - 14:30 p.m.

SISSA, room 128


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Speaker: Jean-Marie Stephan (MPI-PKS Dresden)

Title: Entanglement evolution after inhomogeneous quantum quenches,
and the arctic circle

Abstract:

I consider a simple non-equilibrium problem, where a critical
one-dimensional system is prepared in a state with two different
densities on the left and on the right, and let evolve with a
Hamiltonian that conserves the number of particles. A typical example
would be a fermionic system prepared with different left/right chemical
potentials. The aim is to make analytical predictions regarding the
behavior of correlations as well as the entanglement spreading after
such a quench.
I will discuss attempts at understanding such problems using field
theory. A possible strategy is to study the behavior of the system in
imaginary time, the  real time dynamics being recovered by performing
the Wick rotation. I will show that all degrees of freedom outside a
certain region may freeze in imaginary time, contrary to naive expectations.
This is analogous to the celebrated "arctic circle" phenomenon found
in the study of two-dimensional classical dimer or vertex models.
I will also show that the fluctuating region is described by a
massless field theory with a position-dependent metric, a field theory
in curved space.