9 W Acousto‐Optically Q‐Switched 2 μm Thin‐Disk Laser

We demonstrate an acousto‐optic (AO) Q‐switching Ho:YAG thin disk laser (TDL) at 2 μm with Tm‐fiber laser pumping. Under continuous‐wave operation, the laser delivered a maximum output power of 216.4 W with an optical‐to‐optical efficiency of 43.28, which constitutes the highest power reported for 2 μm TDLs. Under AO Q‐switching, we obtained a maximum average output power of 136.9 W at a repetition rate of 20 kHz, while a maximum pulse energy of 30 mJ at 1 kHz highlighted the strong potential of Ho:YAG TDLs for high‐energy applications. These results further indicate their potential as efficient pump sources for ZnGeP 2 optical parametric oscillators (ZGP‐OPOs), enabling effective wavelength extension into the mid‐ and far‐infrared spectral region.