Intra-cavity side-pumped Ho:YAG laser

Abstract

We present a novel, compact and power scalable Ho:YAG laser based on intracavity side-pumping by a high-power Tm:YLF slab laser. 14W of continuous wave output power is obtained at 2.09µm in the current experiments, with the clear prospect of reaching the 100W regime in a power scaled version.

Room temperature efficient continuous wave and Q-switched Ho:YAG laser double-pass pumped by a diode-pumped Tm:YLF laser

“…Schellhorn reported a CW output power of 9.4 W Ho:YAG thin-disc laser pumped by a diode-pumped Tm:YLF laser [12]. So et al reported a CW output power of 14 W Ho:YAG slab laser intra-cavity side-pumped by a Tm:YLF slab laser [13]. Kieleck et al reported a CW output power of 11.5 W Ho:YAG laser pumped by 20 W Tm:YLF laser [14], corresponding to a thulium-to-holmium optical-tooptical conversion efficiency of 57%, but the system is expensive for the extra cost of an inserted optical diode.…”

2 µm Laser Sources and Their Possible Applications

“…At room temperature a maximum average holmium laser output of 1.6 W with a slope efficiency of 21 % with respect to the incident diode pump power was achieved. In 2006 So et al demonstrated an intra-cavity side-pumped Ho:YAG laser system (So et al, 2006b). A high-power Tm:YLF slab laser (9 x 1.5 x 20 mm³) with an optimised thulium doping concentration of 2 at.…”

Fabrication, properties and laser performance of Ho:YAG transparent ceramic

“…Moreover, direct resonant pumping Ho 5 I 7 manifold offers the advantages of high slope efficiency (70% in Ho:YLiF 4 ) [10], minimal heating due to low quantum defect of less than 10% between pump and laser. The performance of the Ho:YAG single crystal has been widely studied [11,12] and the laser operation has been successfully realized [13][14][15][16][17][18]. Holmium-doped yttrium aluminum garnet (Ho:YAG) ceramic is the promising material of choice for 2.1 m applications due to its well-known excellent thermomechanical properties and advantages compared with Ho:YAG single crystal (for example: ease of fabrication, less cost, mass production, feasibility of large size, high holmium concentration, etc.).…”