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arXiv · 2410.24051

Efficient optimization of plasma surface high harmonic generation by an improved Bayesian strategy

Lili Fan·Ziwei Wang·Chenfei Liao·Jingwei Wang
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Abstract

Plasma surface high-order harmonics generation (SHHG) driven by intense laser pulses on plasma targets enables a high-quality extreme ultraviolet source with high pulse energy and outstanding spatiotemporal coherence. Optimizing the performance of SHHG is important for its applications in single-shot imaging and absorption spectroscopy. In this work, we demonstrate the optimization of laser-driven SHHG by an improved Bayesian strategy in conjunction with particle-in-cell simulations. A traditional Bayesian algorithm is first employed to optimize the SHHG intensity in a two-dimensional space of parameter. Then an improved Bayesian strategy, using the Latin hypercube sampling technique and a dynamic acquisition strategy, is developed to overcome the curse of dimensionality and the risk of local optima in a high-dimensional space optimization. The improved Bayesian optimization approach is efficient and robust in three-dimensionally optimizing the harmonic ellipticity, paving the way for the upcoming SHHG experiments with a considerable repetition rate.

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Lili Fan, Ziwei Wang, Chenfei Liao, Jingwei Wang. 2024-10-31. Efficient optimization of plasma surface high harmonic generation by an improved Bayesian strategy. https://arxiv.org/abs/2410.24051

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