Lehmann G, Spatschek K H
Institut für Theoretische Physik I, <a href="https://ror.org/024z2rq82">Heinrich-Heine-Universität Düsseldorf</a>, D-40225 Düsseldorf, Germany.
Phys Rev E. 2024 Jul;110(1-2):015209. doi: 10.1103/PhysRevE.110.015209.
To avoid damage in high-power laser systems, a chirped plasma-based grating is proposed for compressing laser pulses that have been previously stretched and amplified. This chirped grating is generated through the interaction of chirped pump laser pulses in a plasma slab. Particle-in-cell (PIC) simulations demonstrate that the grating exists for a duration sufficient to be utilized in the final chirped pulse amplification (CPA) stage. The generation of the grating is quite flexible, as several parameters can be adjusted, such as plasma density, chirp, length, and intensity of the pump laser. To begin, the structure of the grating is analyzed in terms of ponderomotive effects of the pump laser pulses. The primary application of the chirped plasma-based grating lies in compressing laser pulses to large amplitudes and short durations after they have been stretched and amplified beforehand. The compression factor is explored in connection with potential grating parameters. Reflectivity and effective bandwidth of chirped plasma gratings are parameters to be optimized. However, the grating spectral bandwidth can only be increased at the expense of reflectivity. The PIC results are made understandable through model calculations based on coupled mode equations.
为避免高功率激光系统中的损伤，提出了一种基于啁啾等离子体的光栅，用于压缩先前已被展宽和放大的激光脉冲。这种啁啾光栅是通过啁啾泵浦激光脉冲在等离子体平板中的相互作用产生的。粒子模拟（PIC）表明，该光栅存在的持续时间足以用于最终的啁啾脉冲放大（CPA）阶段。光栅的产生非常灵活，因为可以调整几个参数，如等离子体密度、啁啾、长度和泵浦激光的强度。首先，根据泵浦激光脉冲的有质动力效应分析光栅的结构。基于啁啾等离子体的光栅的主要应用在于在激光脉冲预先展宽和放大之后将其压缩到高振幅和短持续时间。结合潜在的光栅参数探索压缩因子。啁啾等离子体光栅的反射率和有效带宽是需要优化的参数。然而，光栅光谱带宽只能以反射率为代价来增加。通过基于耦合模方程的模型计算，使PIC结果易于理解。
