Lang L, Bauer C P, Phillips C R, Keller U
Opt Express. 2021 Oct 25;29(22):36321-36327. doi: 10.1364/OE.440189.
We present a high power optical parametric oscillator (OPO) synchronously pumped by the second-harmonic of a modelocked 1030-nm thin-disk laser (TDL) oscillator. The OPO delivers an average power of 51.1 W around degeneracy (1030 nm) with a 10.2-MHz repetition-rate. After extra-cavity dispersion compensation using dispersive mirrors, we obtain a pulse duration of 169 fs, which is 4.6× shorter than the TDL pulse duration of 770 fs. The TDL has 250 W average power, which is converted to 215 W at the second-harmonic. Hence, the OPO exhibits a high photon conversion efficiency of 47% (ratio of signal photons to 515-nm pump photons). Moreover, the OPO generates a peak power of 26.2 MW, which is very similar to the 28.0-MW peak power of the TDL. To facilitate continuous tuning around degeneracy and convenient extraction of the pump and idler beams, the OPO is operated in a noncollinear configuration. A linear cavity configuration was chosen since it offers easy alignment and straightforward cavity length tuning. To the best of our knowledge, this source has the highest average power generated by any ultrafast OPO, and the shortest pulse duration for any >5-W OPO. This result is an important step to adding wavelength tunability to high power Yb-based laser sources without the complexity of either laser or parametric amplifier systems.
我们展示了一种由锁模1030纳米薄片激光器（TDL）振荡器的二次谐波同步泵浦的高功率光学参量振荡器（OPO）。该OPO在简并点（1030纳米）附近输出平均功率为51.1瓦，重复频率为10.2兆赫兹。在使用色散镜进行腔外色散补偿后，我们获得了169飞秒的脉冲持续时间，比TDL的770飞秒脉冲持续时间短4.6倍。TDL的平均功率为250瓦，在二次谐波处转换为215瓦。因此，OPO表现出47%的高光子转换效率（信号光子与515纳米泵浦光子的比率）。此外，OPO产生的峰值功率为26.2兆瓦，与TDL的28.0兆瓦峰值功率非常相似。为了便于在简并点附近进行连续调谐以及方便地提取泵浦光和闲频光，OPO采用非共线配置运行。选择线性腔配置是因为它易于对准且腔长调谐简单。据我们所知，该光源是所有超快OPO产生的平均功率最高的，也是所有功率大于5瓦的OPO中脉冲持续时间最短的。这一结果是在不增加激光或参量放大器系统复杂性的情况下，为高功率镱基激光源增加波长可调谐性的重要一步。
