High-quality stable electron beams from laser wakefield acceleration in high density plasma

R. Rathore,P. D. Gupta,P. A. Naik,J. A. Chakera,B. S. Rao,A. Moorti

doi:10.1103/physrevstab.17.011301

Abstract

High-quality, stable electron beams are produced from self-injected laser wakefield acceleration using the interaction of moderate 3 TW, 45 fs duration Ti:sapphire laser pulses with high density ($>5\ifmmode\times\else\texttimes\fi{}{10}^{19}\text{ }\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}3}$) helium gas jet plasma. The electron beam has virtually background-free quasimonoenergetic distribution with energy ${35.6}_{\ensuremath{-}2.5}^{+3.9}\text{ }\text{ }\mathrm{MeV}$, charge ${3.8}_{\ensuremath{-}1.2}^{+2.8}\text{ }\text{ }\mathrm{pC}$, divergence and pointing variation $\ensuremath{\sim}10\text{ }\text{ }\mathrm{mrad}$. The stable and high quality of the electron beam opens an easy way for applications of the laser wakefield accelerator in the future, particularly due to the widespread availability of sub-10 TW class lasers with a number of laser plasma laboratories around the world.

Highlights

Laser wakefield acceleration is currently widely pursued as a promising technique to realize compact high-energy electron accelerators in the future [1]
In the blowout" regime [2], which is known as the “bubble” regime, a relativistically intense, ultrashort laser pulse propagating in underdense plasma blows out the plasma electrons radially by the ponderomotive force forming a near spherical electron bubble that propagates with the laser pulse with a velocity close to c
We report the demonstration of stable and high-quality electron beams from self-injected laser wakefield acceleration, using a relatively much lower power (3 TW) and longer duration (45 fs) Ti:sapphire laser pulses interacting with high density (5.8 × 1019 cm−3) plasma

Summary

Introduction

Laser wakefield acceleration is currently widely pursued as a promising technique to realize compact high-energy electron accelerators in the future [1]. Recent studies in the bubble regime, using 40–50 TW power or few cycle laser pulses, and plasma density ≤ 2 × 1019 cm−3 (cτL ≤ λp), have shown self-injected quasimonoenergetic electron beams of ∼300 MeV or 25 MeV, with apparently no low-energy background electrons [9,10].

Results

Conclusion