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arXiv · 2506.19824

Laser Wakefield Acceleration Driven by a Discrete Flying Focus

Jacob R. Pierce·Kyle G. Miller·Fei Li·John P. Palastro·Warren B. Mori
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Abstract

Laser wakefield acceleration (LWFA) may enable the next generation of TeV-scale lepton colliders. Reaching such energies will likely require multiple LWFA stages to overcome limitations on the energy gain achievable in a single stage. The use of stages, however, introduces challenges such as alignment, adiabatic matching between stages, and a lower average accelerating gradient. Here, we propose a discrete flying focus that can deliver higher energy gain in a single stage, thereby reducing the number of stages required for a target energy. A sequence of laser pulses with staggered focal points and delays drives a plasma wave in which an electron beam experiences a near-constant accelerating gradient over distances beyond those attainable with a conventional pulse. Simulations demonstrate that a discrete flying focus with a total energy of 150 J can transfer 40 GeV per electron to a 50-pC beam in a single 30-cm stage, corresponding to 50 dephasing lengths.

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Jacob R. Pierce, Kyle G. Miller, Fei Li, John P. Palastro, Warren B. Mori. 2025-06-24. Laser Wakefield Acceleration Driven by a Discrete Flying Focus. https://arxiv.org/abs/2506.19824

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