AUTHOR=Zhang Ziyue , Ma Junyi , Zhao Guodong , Shao Xiaodong , Zheng Yunzhong , Han Hainian , Wei Zhiyi 

TITLE=Sub-100 fs watt-level Kerr-lens mode-locked Yb:CaYAlO4 laser with a gigahertz repetition rate

JOURNAL=Frontiers in Physics

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2023.1116054

DOI=10.3389/fphy.2023.1116054

ISSN=2296-424X

ABSTRACT=<p>We report a 1.04 GHz high-power Kerr-lens mode-locked Yb:CaYAlO<sub>4</sub> laser pumped by a single-mode fiber laser at 976 nm. Based on a bow-tie cavity, stable unidirectional mode-locked operation is obtained with an output coupler of 1.6%. The oscillator delivers pulses with an average power of 1.46 W and with the pulse duration of 99 fs, which, to the best of our knowledge, is the first gigahertz-level Kerr-lens mode-locked laser based on the Yb:CaYAlO<sub>4</sub> gain medium. We believe that the watt-level solid-state femtosecond laser at GHz would be an excellent source for developing time-resolved broadband dual-comb spectroscopy.</p>