Ion acceleration 'via' relativistic self induced transparency in subwavelength target

TL;DR

This paper investigates how target thickness influences relativistic self-induced transparency (RSIT) and demonstrates ion acceleration to ~100 MeV using the electrostatic field generated by RSIT in subwavelength targets, proposing a scaling law for optimal conditions.

Contribution

It introduces a new understanding of target thickness effects on RSIT and presents a scaling law for optimizing ion acceleration in subwavelength targets.

Findings

Target density threshold increases for subwavelength targets.

Ion energies up to ~100 MeV achieved from low-density layers.

Low-density layers enhance ion energy spectra.

Abstract

In this work we have studied the effect of target thickness on relativistic self-induced transparency (RSIT) and found out that for subwavelength targets the corresponding threshold target density (beyond which target is opaque to incident laser pulse of a given intensity) increases. The accelerating longitudinal electrostatic field created by RSIT from subwavelength target is used to accelerate the ion bunch from a thin, low density layer behind the main target to $\sim$ 100 MeV. A suitable scaling law for optimum laser and target conditions is also deduced. The word `via' in the title signifies the fact that we are interested in acceleration of ions from the layer placed behind the target. It is also being observed that as per as energy spectrum is concerned; an extra low density layer is advantageous than relying on target ions alone.