Photonics Institute, Vienna University of Technology, Gusshausstrasse 27/387, A-1040 Vienna, Austria.
Opt Lett. 2012 Jul 1;37(13):2547-9. doi: 10.1364/OL.37.002547.
We demonstrate shaping of high-energy broadband Yb amplifier pulses for the generation of a (sub)picosecond top-hat temporal pulse profile that significantly improves pumping efficiency of an optical parametric amplifier (OPA). Phase-only modulation is applied by an acousto-optic programmable dispersion filter. This simple scheme is scalable to a high average power due to a relatively broad bandwidth of the Yb:CaF(2) gain medium used in the amplifier that supports a sub-150-fs transform-limited pulse duration. Additionally we show that OPA seeding with supercontinuum remains possible because top-hat-shaped pulses passed through a glass block recompress to ≈200 fs with minimum satellite production.
我们演示了高能宽带 Yb 放大器脉冲的整形，以产生（亚）皮秒平顶时间脉冲轮廓，从而显著提高光学参量放大器（OPA）的泵浦效率。通过声光可编程色散滤波器实现纯相位调制。由于在放大器中使用的 Yb:CaF2 增益介质具有相对较宽的带宽，支持亚 150fs 的变换极限脉冲持续时间，因此这种简单的方案可扩展到高平均功率。此外，我们还表明，超连续谱的 OPA 种子仍然是可行的，因为通过玻璃块的平顶脉冲再压缩到 ≈200fs，同时产生最小的卫星。
