Transient electric fields in laser plasmas observed by proton streak deflectometry

TL;DR

This paper introduces a new proton streak deflectometry technique that captures the evolution of transient electric fields in laser-irradiated foils over nanoseconds, revealing longer-lasting and spatially extensive fields than previously observed.

Contribution

The paper presents a novel continuous-time proton imaging method for measuring transient electric fields in laser plasmas, enabling detailed temporal and spatial analysis.

Findings

Electric fields up to 10^8 V/m observed

Fields extend over millimeter scales

Fields last nanoseconds, longer than laser pulse duration

Abstract

A novel proton imaging technique was applied which allows a continuous temporal record of electric fields within a time window of several nanoseconds. This "proton streak deflectometry" was used to investigate transient electric fields of intense (~ 10^17 W/cm^2) laser irradiated foils. We found out that these fields with an absolute peak of up to 10^8 V/m extend over millimeter lateral extension and decay at nanosecond duration. Hence, they last much longer than the (~ ps) laser excitation, and extend much beyond the laser irradiation focus.