A near-Stokes limit Ho:CaYAlO ₄ laser in room temperature

We show a high-slope-efficiency Ho:CaYAlO laser using conventional watercooling method.Under an L-shaped laser resonator cavity with an overlapping efficiency greater than 98%, a maximum output power of 18.64 W at 2081 nm was achieved when the absorbed pump power was 26.83 W. By linear-fitting, the slope-efficiency relative to the absorbed pump power of 90.6%.Under the maximum output power, the beam quality factor is lower than 1.25 and the root-mean-square stability about 0.42%.Additionally, we validated the output performances of the laser in acousto-optic Q-switched mode under high-slope-efficiency condition.At a pulse repetition rate of 10 kHz, a maximum average output power of 18.26 W and a narrowest pulse width of 40.1 ns were achieved, corresponding to a pulse energy, peak power, and slope-efficiency of 1.83 mJ, 45.54 kW, Downloaded from https://www.cambridge.org/core.26 May 2026 at 07:10:59, subject to the Cambridge Core terms of use.Accepted Manuscript 2 and 87.7%, respectively.To this knowledge, this laser may be the highest-slope-efficiency for the Ho-doped solid-state laser using conventional water-cooling.