Diode-side-pumped, passively Q-switched Yb:LuAG laser

• We elaborated passively Q-switched Yb:LuAG laser operating in room temperature
• We proposed an analytical–experimental approach to design efficient Q-switched laser
• Pulse energy of 10.1 mJ with 4 ns pulse duration and 2.5 MW peak power was achieved

A high-gain, diode-side-pumped Yb:LuAG slab laser was designed and investigated for use at room temperature. Pumping occurred from a fast-axis collimated 2D laser diode stack emitting at a wavelength of 970 nm, with 0.8 J over a duration of 0.8 ms. The pump scheme, which enabled efficient mode matching and high gain, was analysed and experimentally verified for different dopant levels. An energy of 100 mJ with 23% slope efficiency in a near fundamental mode was achieved in the free-running regime. A peak power of 2.5 MW and a pulse energy of 10.1 mJ were demonstrated in passive Q-switching by means of a Cr:YAG saturable absorber with 39% initial transmission. The study defined the indications for optimizing such a system.