Probing false vacuum decay on a cold-atom gauge-theory quantum simulator

TL;DR

This paper demonstrates how a cold-atom quantum simulator can be used to study false vacuum decay and pair production in a lattice gauge theory, providing insights into non-perturbative quantum field phenomena.

Contribution

It introduces an experimental setup for simulating pair production in a 1+1D U(1) lattice gauge theory with tunable background fields, enabling controlled studies of non-equilibrium dynamics.

Findings

Able to tune pair production rate via background field adjustments

Observed excitation peaks analogous to bosonic modes in the Schwinger model

Opened pathways for quantum simulation of far-from-equilibrium quantum field phenomena

Abstract

In the context of quantum electrodynamics, the decay of false vacuum leads to the production of electron-positron pair, a phenomenon known as the Schwinger effect. In practical experimental scenarios, producing a pair requires an extremely strong electric field, thus suppressing the production rate and making this process very challenging to observe. Here we report an experimental investigation, in a cold-atom quantum simulator, of the effect of the background field on pair production from the infinite-mass vacuum in a $1+1$D $\mathrm{U}(1)$ lattice gauge theory. The ability to tune the background field allows us to study pair production in a large production rate regime. Furthermore, we find that the energy spectrum of the time-evolved observables in the zero mass limit displays excitation peaks analogous to bosonic modes in the Schwinger model. Our work opens the door to quantum-simulation experiments that can controllably tune the production of pairs and manipulate their far-from-equilibrium dynamics.