Thermal quench at finite 't Hooft coupling

H Ebrahim,M Ali-Akbari,S Heshmatian

doi:10.1016/j.nuclphysb.2016.02.003

Abstract

Using holography we have studied thermal electric field quench for infinite and finite 't Hooft coupling constant. The set-up we consider here is D7-brane embedded in (α′ corrected) AdS-black hole background. It is well-known that due to a time-dependent electric field on the probe brane, a time-dependent current will be produced and it will finally relax to its equilibrium value. We have studied the effect of different parameters of the system on equilibration time. As the most important results, for massless fundamental matter, we have observed a universal behaviour in the rescaled equilibration time in the very fast quench regime for different values of the temperature and α′ correction parameter. It seems that in the slow quench regime the system behaves adiabatically. We have also observed that the equilibration time decreases in finite 't Hooft coupling limit.

Highlights

ArXiv:1510.07974v1 [hep-th] 27 Oct 2015 study [8]
We consider a general class of black hole metrics of the form ds2 = Gttdt2 + Gxxdx2 + Gzzdz2 + GssdΩ25, (1)
In order to add the fundamental matter to the field theory, it is well known that D-branes must be added to the background in the probe limit which means that the branes do not back-react on the background

Summary

TIME-DEPENDENT EXTERNAL ELECTRIC FIELD

In order to add the fundamental matter to the field theory, it is well known that D-branes must be added to the background in the probe limit which means that the branes do not back-react on the background. To have a time-dependent electric field along one of the field theory directions, say x, we need to consider Ax(t, z) to be non-zero. We have assumed that φ = 0 and θ = 0 which means we are dealing with massless fundamental degrees of freedom As it is clear the x-component of the gauge field is not a function of x since we would like to. Similar to the near boundary expansion in the static external electric field case [9], the time-dependent current in the field theory is given by the second derivative of a with respect to z at the boundary j(t) ∝ ∂z2a(t, z = 0)

ENERGY INJECTION AND EQUILIBRATION

Infinite t’Hooft Coupling Constant

Finite t’Hooft Coupling Constant

Finite t’Hooft Coupling