Efficient electro-optically Q-switched Ho:GdTaO4 laser recycle-pumped by a wavelength-narrowed laser diode

We present a diode-pumped electro-optically (EO) Q-switched Ho:GdTaO4 (Ho:GTO) laser. The langasite (La3Ga5SiO14, LGS) crystal was utilised as the EO Q-switch. With a repetition rate of 2 kHz, a maximum pulse energy of 1.46 mJ at 2067.6 nm and a minimum pulse width of 12 ns were realised at an absorbed pump power of 17.1 W, corresponding to a maximum peak power of as high as 121.3 kW. Moreover, at the maximum average output power, the beam quality factors of the diode-pumped EO Q-switched Ho:GTO laser were estimated to be 1.66 in the x-direction and 1.52 in the y-direction.