Barrier control in tunneling e^+ e^- photoproduction

TL;DR

This paper analyzes electron-positron pair production via tunneling in a setup with colliding laser fields and a relativistic nucleus, showing that adjusting the weak field's frequency can make the process observable with current technology.

Contribution

It provides an analytical calculation of tunneling pair production rates in a novel laser-nucleus setup, highlighting how frequency tuning reduces the tunneling barrier.

Findings

Pair production rate is analytically derived under specific field conditions.

Adjusting the weak field's frequency significantly lowers the tunneling barrier.

The process is shown to be observable with existing experimental technology.

Abstract

Tunneling electron-positron pair production is studied in a new setup in which a strong low-frequency and a weak high-frequency laser field propagate in the same direction and collide head-on with a relativistic nucleus. The electron-positron pair production rate is calculated analytically in the limit in which in the nucleus rest frame the strong field is undercritical and the frequency of the weak field is below and close to the pair production threshold. By changing the frequency of the weak field one can reduce the tunneling barrier substantially. As a result tunneling pair production is shown to be observable with presently available technology.