Extreme plasma states in laser-governed vacuum breakdown

TL;DR

This paper demonstrates that using optimally configured petawatt-class lasers, it is possible to generate extremely dense plasma states exceeding the relativistic critical density, opening new avenues in nonlinear plasma physics and laboratory astrophysics.

Contribution

The study introduces a method to surpass the relativistic critical density limit using tightly focused laser fields, supported by 3D QED-PIC simulations showing densities over 10^{25} cm^{-3}.

Findings

Achieved plasma densities over 10^{25} cm^{-3}.

Tightly focused laser fields enable generation of extreme plasma states.

Control of initial target parameters allows reaching these states.

Abstract

Triggering vacuum breakdown at the upcoming laser facilities can provide rapid electron-positron pair production for studies in laboratory astrophysics and fundamental physics. However, the density of the emerging plasma should seemingly stop rising at the relativistic critical density, when the plasma becomes opaque. Here we identify the opportunity of breaking this limit using optimal beam configuration of petawatt-class lasers. Tightly focused laser fields allow plasma generation in a small focal volume much less than ${\lambda}^3$, and creating extreme plasma states in terms of density and produced currents. These states can be regarded as a new object of nonlinear plasma physics. Using 3D QED-PIC simulations we demonstrate the possibility of reaching densities of more than $10^{25}$ cm$^{-3}$, which is an order of magnitude higher than previously expected. Controlling the process via the initial target parameters gives the opportunity to reach the discovered plasma states at the upcoming laser facilities.