A continuous-wave b-cut Tm, Ho:YAlO3 laser with a 15 W output pumped by two laser diodes

A high power and efficiency b-cut Tm, Ho:YAlO3 (YAP) laser is reported in this letter. The laser operated in continuous-wave (CW) mode at 2.12 μm. The Tm, Ho:YAP crystal was cooled at a temperature of 77 K and pumped by two fibre-coupled laser diodes with centre output wavelengths of 794.1 and 794.0 nm. A 15.0 W output power was obtained at a 155 mm physical cavity length with an optical–optical conversion efficiency of 39.2%, corresponding to a slope efficiency of 41.1%.