High-repetition-rate, all-reflective optical guiding and electron acceleration in helium using an off-axis axicon

TL;DR

This paper demonstrates high-repetition-rate laser wakefield acceleration in helium using an all-reflective optical setup with an off-axis axicon, achieving stable electron beams up to 5 GeV.

Contribution

It introduces a novel all-reflective optical configuration enabling efficient, stable LWFA at high repetition rates without modifying the laser system.

Findings

Achieved electron energies approaching 5 GeV.

Guided electron beams at 0.2 Hz and guiding at 3.3 Hz.

Stabilized electron pointing and increased energy gain.

Abstract

We present recent results on high-power guiding and laser wakefield acceleration (LWFA) in the ELBA beamline at ELI Beamlines, using the L3-HAPLS laser system (13 J, 30 fs, 0.2 Hz). By employing self-waveguiding in a 20 cm plasma channel in helium, we achieved stable acceleration of electron beams to energies approaching 5 GeV. A novel all-reflective optical setup, including an off-axis reflective axicon, enabled efficient acceleration at 0.2 Hz and guiding at repetition rates up to 3.3 Hz. This compact single laser, single compressor implementation of plasma channels for electron acceleration stabilizes electron pointing and enhances energy gain without requiring modifications to the laser system, paving the way for broader adoption of the technology across user facilities.