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Automated optimization of microbunching for seeded free-electron laser schemes

Zihan Wang, Zhenghe Bai*, Qika Jia†, Zhouyu Zhao, and Guangyao Feng‡

  • *Contact author: baizhe@ustc.edu.cn
  • †Contact author: jiaqk@ustc.edu.cn
  • ‡Contact author: fenggy@ustc.edu.cn
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Phys. Rev. Accel. Beams 29, 113401 – Published 10 November, 2026

DOI: https://doi.org/10.1103/bqll-w87s

Abstract

Seeded free-electron lasers (FELs) have become indispensable tools across numerous scientific fields, owing to their high coherence and stability. Unlike self-amplified spontaneous emission, seeded FELs require a prebunched electron beam to be formed upstream of the radiator, enabling the subsequent generation of fully coherent radiation. This bunching process can be numerically calculated based on the specific components and their parameters used. To facilitate the discovery and optimization of such FELs, in this paper we present an automated optimization method for the microbunching process in seeded FEL schemes. It is demonstrated that the method can automatically reproduce established seeded FELs, such as echo-enabled harmonic generation, eliminating the need for prior physical analysis. Moreover, the method yields new findings in seeded FELs that go beyond mere replication. By incorporating more kinds of components and exploring a broader set of optimization objectives, the optimization can be extended to explore more possibilities.

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Phys. Rev. Accel. Beams 29, 113401– Published 10 November, 2026
  • Received 16 January 2026
  • Accepted 28 October 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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