Schwinger Effect and Negative Differential Conductivity in Holographic Models

TL;DR

This paper investigates how the Schwinger effect influences conductivity in strongly coupled systems using holography, revealing that it induces a real conductivity in insulators and can lead to negative differential conductivity.

Contribution

It demonstrates the impact of the Schwinger effect on conductivity within holographic models, specifically showing negative differential conductivity in the Sakai-Sugimoto model.

Findings

Schwinger effect induces a real conductivity in insulating phases.

Negative differential conductivity observed in certain parameter regimes.

Holographic computation captures one-loop effects on flavor branes.

Abstract

The consequences of the Schwinger effect for conductivity is computed for strong coupling systems using holography. The one loop diagram on the flavor brane introduces an $O({\lambda \over N_c})$ imaginary part in the effective action for a Maxwell flavor gauge field. This in turn introduces a real conductivity in an otherwise insulating phase of the boundary theory. Moreover in certain regions of parameter space the differential conductivity is negative. This is computed in the context of the Sakai-Sugimoto model.