Probing Klein tunneling through quantum quenches

TL;DR

This paper investigates how quantum quenches in a relativistic fermion system can reveal Klein tunneling effects, showing particle production and non-equilibrium steady states that could be observed experimentally.

Contribution

It analytically characterizes particle production and steady states resulting from inhomogeneous quantum quenches related to Klein tunneling in one-dimensional relativistic fermions.

Findings

Particle production occurs at a constant rate during evolution.

The long-time state is a non-equilibrium steady state.

Potential for experimental observation of Klein tunneling effects.

Abstract

We study the interplay between an inhomogeneous quantum quench of the external potential in a system of relativistic fermions in one dimension and the well-known Klein tunneling. We find that the large time evolution is characterized by particle production at a constant rate which we derive analytically. The produced particles can be physically interpreted according to a semiclassical picture and the state reached in the long time limit can be classified as a non-equilibrium-steady-state. Such a quantum quench can be used in order to observe macroscopic effects of Klein tunneling in transport, raising the possibility of an experimental implementation.