Ho:KLu(WO4)2 Microchip Laser Q-Switched by a PbS Quantum-Dot-Doped Glass

We report on passive Q-switching of a Ho:KLu(WO
₄
)
₂
(Ho:KLuW) microchip laser in-band-pumped by a Tm:KLuW laser at
$\sim 1.96\mu \text{m}$
. As a saturable absorber, PbS-quantum-dot-doped glass was used which exhibits a saturation intensity of
$\sim 3$
MW/cm
$^{\mathrm {{2}}}$
near 2
$\mu \text{m}$
. Maximum average output power of 84 mW was achieved from the Ho laser at 2.061
$\mu \text{m}$
with a slope efficiency of 42% (with respect to the absorbed pump power). The shortest pulse duration was 30 ns. In the continuous-wave mode, the maximum output power of the Ho laser reached 530 mW at 2.08
$\mu \text{m}$
with a slope efficiency of 88%.