Amplification and generation of ultra-intense twisted laser pulses via stimulated Raman scattering.

J Vieira,R Bingham,R M G M Trines,P Norreys,L O Silva,R A Fonseca,E P Alves,J T Mendonça

doi:10.1038/ncomms10371

Abstract

Twisted Laguerre–Gaussian lasers, with orbital angular momentum and characterized by doughnut-shaped intensity profiles, provide a transformative set of tools and research directions in a growing range of fields and applications, from super-resolution microcopy and ultra-fast optical communications to quantum computing and astrophysics. The impact of twisted light is widening as recent numerical calculations provided solutions to long-standing challenges in plasma-based acceleration by allowing for high-gradient positron acceleration. The production of ultra-high-intensity twisted laser pulses could then also have a broad influence on relativistic laser–matter interactions. Here we show theoretically and with ab initio three-dimensional particle-in-cell simulations that stimulated Raman backscattering can generate and amplify twisted lasers to petawatt intensities in plasmas. This work may open new research directions in nonlinear optics and high–energy-density science, compact plasma-based accelerators and light sources.

Highlights

Twisted Laguerre–Gaussian lasers, with orbital angular momentum and characterized by doughnut-shaped intensity profiles, provide a transformative set of tools and research directions in a growing range of fields and applications, from super-resolution microcopy and ultra-fast optical communications to quantum computing and astrophysics
At intensities beyond material breakdown thresholds, it has been recently shown through theory and simulations that intense and short twisted laser beams could excite strongly nonlinear plasma waves suitable for high-gradient positron acceleration in plasma accelerators[10]
Other routes may be used to produce highintensity orbital angular momentum (OAM) laser pulses, for instance, by placing spiral phase plates either at the start or at the end of a laser amplification chain[16,17], the use of plasmas can potentially lead to the amplification of OAM light to very high powers and intensities

Summary

Introduction

Twisted Laguerre–Gaussian lasers, with orbital angular momentum and characterized by doughnut-shaped intensity profiles, provide a transformative set of tools and research directions in a growing range of fields and applications, from super-resolution microcopy and ultra-fast optical communications to quantum computing and astrophysics. We demonstrate that stimulated Raman scattering processes can generate and amplify OAM light even in scenarios where no net OAM is initially present To this end, we use an analytical theory, valid for arbitrary transverse laser field envelope profiles, complemented by the first three-dimensional (3D) ab initio particle-in-cell (PIC) simulation of the process using the PIC code OSIRIS19, considering that the optical medium is a plasma. Starting from recent experimental and theoretical advances[20,21,22], our simulations and theoretical developments show that stimulated Raman processes could pave the way to generate OAM light in nonlinear optical media and that the nonlinear optics of plasmas[23,24] could provide a path to generate and amplify OAM light to relativistic intensities[25,26,27,28]

Methods

Results

Conclusion