A compact high power diode side-pumped 2.09 μm Tm,Ho:YAG laser

Abstract We demonstrate a high power compact continuous-wave diode side-pumped Tm,Ho:YAG all solid-state laser at room temperature. A high dopant concentration ratio of Tm,Ho:YAG (3 at.% Tm 3+ , 0.1 at.% Ho 3+ ) crystal rod with laser diode (LD) side-pumped architecture is employed as a laser head. With a single laser head in a plane-parallel short cavity, a maximum 57 W output power is obtained at a temperature of 19 °C, corresponding to an optical-to-optical efficiency of 10.6% and a slope efficiency of 16.6%. To the best of our knowledge, this is the highest output power of LD-pumped Tm,Ho co-doped laser operating at room temperature. This laser system also exhibits excellent power stability in 90 min, making it widely applicable in various fields.