Modsching Norbert, Drs Jakub, Fischer Julian, Paradis Clément, Labaye François, Gaponenko Maxim, Kränkel Christian, Wittwer Valentin J, Südmeyer Thomas
Opt Express. 2019 May 27;27(11):16111-16120. doi: 10.1364/OE.27.016111.
We investigate power-scaling of a Kerr lens mode-locked (KLM) Yb:LuO thin-disk laser (TDL) oscillator operating in the sub-100-fs pulse duration regime. Employing a scheme with higher round-trip gain by increasing the number of passes through the thin-disk gain element, we increase the average power by a factor of two and the optical-to-optical efficiency by a factor of almost three compared to our previous sub-100-fs mode-locking results. The oscillator generates pulses with a duration of 95 fs at 21.1 W average power and 47.9 MHz repetition rate. We discuss the cavity design for continuous-wave and mode-locked operation and the estimation of the focal length of the Kerr lens. Unlike to usual KLM TDL oscillators, an operation at the edge of the stability zone in continuous-wave operation is not required. This work shows that KLM TDL oscillators based on the gain material Yb:LuO are an excellent choice for power-scaling of laser oscillators in the sub-100-fs regime, and we expect that such lasers will soon operate at power levels in excess of hundred watts.
我们研究了工作在脉冲持续时间低于100飞秒范围内的克尔透镜锁模（KLM）镱：镥酸镧（Yb:LuO）薄片激光器（TDL）振荡器的功率缩放特性。通过增加薄片增益元件的往返次数，采用一种具有更高往返增益的方案，与我们之前低于100飞秒的锁模结果相比，我们将平均功率提高了两倍，光光效率提高了近三倍。该振荡器产生的脉冲持续时间为95飞秒，平均功率为21.1瓦，重复频率为47.9兆赫兹。我们讨论了连续波和锁模运转的腔设计以及克尔透镜焦距的估算。与通常的KLM TDL振荡器不同，连续波运转时不需要在稳定区边缘工作。这项工作表明，基于增益介质Yb:LuO的KLM TDL振荡器是低于100飞秒范围内激光振荡器功率缩放的极佳选择，并且我们预计此类激光器很快将在超过百瓦的功率水平下运转。
