A high-energy, high-beam-quality, high-contrast picosecond optical parametric chirped-pulse amplification (ps-OPCPA) laser system was demonstrated. The pulse from a femtosecond oscillator was stretched to 4 ps, after which it was amplified from 140 pJ to 600 µJ by an 8 ps/6 mJ pump laser in two non-collinear OPCPA stages. The total gain was >10⁶, and the root mean square of the energy stability of the laser system was 1.6% in 10 h. The contrasts of the solid and fiber mode-locked femtosecond oscillator-seeded ps-OPCPA systems were compared, and a signal-to-noise ratio of >10¹¹ was achieved. Using this system, the contrast of the front end in high-power picosecond petawatt laser facility was improved by ∼40 dB to >10¹¹, beyond ∼200 ps ahead of the main pulse with an output level of 60 mJ.

中文翻译：

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基于ps-OPCPA种子系统的大功率PB激光设备中的高对比度OPCPA前端

演示了一种高能量，高光束质量，高对比度的皮秒光学参量chi脉冲放大（ps-OPCPA）激光系统。飞秒振荡器产生的脉冲被延长到4 ps，然后在两个非共线的OPCPA级中，由8 ps / 6 mJ泵浦激光器将其从140 pJ放大到600 µJ。总增益> 10 ⁶，并且激光系统的能量稳定性的均方根在10小时内为1.6％。比较了固态和光纤锁模飞秒振荡器与ps-OPCPA系统的对比，信噪比> 10 ¹¹。使用该系统，大功率皮秒皮瓦激光设备前端的对比度提高了约40 dB，达到了> 10 ¹¹，比主脉冲提前约200 ps，输出电平为60 mJ。