First Electron Acceleration in a Tunable-Velocity Laser Wakefield

Abstract

We present the first experimental confirmation that a laser-wakefield accelerator produced by a flying focus pulse is able to maintain the coherent structures necessary to accelerate electrons to relativistic energies. Through a combination of spatio-temporal near-field shaping of the beam and focusing with an axiparabola - a long-focal-depth mirror that produces a quasi-Bessel beam - the propagation velocity of the wakefield is tuned to control the maximum electron energy achievable. The experimental data are supported by advanced optical and particle-in-cell simulations and are aligned with a simplified analytical model. Together, the results significantly strengthen the case for the flying-focus wakefield as a strategy for mitigating dephasing in laser-wakefield acceleration.

9 pages, 3 figures

References in corpus (11)

• Generating multi-GeV electron bunches using single stage laser wakefield acceleration in a 3D nonlinear regime
• A spectral, quasi-cylindrical and dispersion-free Particle-In-Cell algorithm
• Nonlinear laser driven donut wakefields for positron and electron acceleration
• Observation of beam loading in a laser-plasma accelerator
• Elimination of Numerical Cherenkov Instability in flowing-plasma Particle-In-Cell simulations by using Galilean coordinates
• Experimental demonstration of mice tumor control with a laser-accelerated high-energy electron radiotherapy prototype
• Use of spatiotemporal couplings and an axiparabola to control axial energy deposition velocity
• Measurement and Control of Main Spatio-Temporal Couplings in a CPA Laser Chain
• Spatiotemporal pulse characterization with far-field beamlet cross-correlation
• Simple few-shot method for spectrally resolving the wavefront of an ultrashort laser pulse
• First direct observation of a wakefield generated with structured light