# Laser Pulse Sharpening with Electromagnetically Induced Transparency in Plasma

## TL;DR

This paper introduces a novel plasma shutter technique controlled by laser pulses, enabling the generation of ultra-sharp laser pulses through a process similar to electromagnetically-induced transparency, with potential advantages over plasma mirrors.

## Contribution

It presents a new method for laser pulse sharpening using plasma transparency controlled by a laser, extending capabilities beyond traditional plasma mirror regimes.

## Key findings

- Numerical simulations show sub-picosecond pulse wavefronts are achievable.
- The technique operates in regimes inaccessible to plasma mirrors.
- It enables propagation of low-frequency pulses through high-density plasma.

## Abstract

We propose a laser-controlled plasma shutter technique to generate sharp laser pulses using a process analogous to electromagnetically-induced transparency in atoms. The shutter is controlled by a laser with moderately strong intensity, which induces a transparency window below the cutoff frequency, and hence enables propagation of a low frequency laser pulse. Numerical simulations demonstrate it is possible to generate a sharp pulse wavefront (sub-ps) using two broad pulses in high density plasma. The technique can work in a regime that is not accessible by plasma mirrors when the pulse pedestals are stronger than the ionization intensity.