Laser pulse compression by a density gradient plasma for exawatt to zettawatt lasers

TL;DR

This paper introduces a plasma-based laser pulse compression method utilizing a density gradient, enabling significant pulse shortening suitable for ultra-high power laser applications like exawatt to zettawatt scales.

Contribution

The authors propose a novel plasma density gradient scheme for laser pulse compression, demonstrated through 1D PIC simulations achieving a 225-fold compression ratio.

Findings

Laser pulse compressed from 2.35 ps to 10.3 fs

Achieved compression ratio of 225

Potential to reach exawatt to zettawatt laser powers

Abstract

We propose a new method for laser pulse compression that uses the spatially varying dispersion of a plasma plume with a density gradient. This novel scheme can be used to compress ultrahigh power lasers. A long, negatively frequency-chirped, laser pulse reflects off the plasma ramp of an over-dense plasma. As the density increases longitudinally the high frequency photons at the leading part of the laser pulse propagates more deeply than low frequency photons, the pulse is compressed in a similar way to compression off a chirped mirror. Proof-of-principle simulations, using a one-dimensional (1-D) particle-in-cell (PIC) simulation code demonstrates the compression of 2.35 ps laser pulse to 10.3 fs, with a compression ratio of 225. As plasmas is robust and resistant to high intensities, unlike gratings in a chirped-pulse amplification (CPA) technique [1], the method could be used as a compressor to reach exawatt or zettawatt peak power lasers.