H Yang

The performance of 1329 nm CW and passively Q-switched Nd:LGGG laser with low Lu-doping level

The Nd:(LuxGd1?x)3Ga5O12 (Nd:LGGG) laser operating at 1329?nm in both the continuous wave (CW) and the passively Q-switched (PQS) regimes has been successfully demonstrated. With an absorbed pump power of 18.8?W, a maximum CW output power of 3.7?W was obtained, corresponding to an optical?optical conversion efficiency of 19.6% and a slope efficiency of 20.9%. The PQS laser performance was obtained using a V3+:YAG crystal as the saturable absorber. The maximum average output power, shortest pulse width, largest pulse energy and highest peak power were 0.75?W, 25.9?ns, 43.6??J and 1.7?kW, respectively. The results indicate that a Nd:LGGG crystal with a low Lu-doping level (0.66?at.%) could be a novel potential laser gain medium suitable for laser diode pumping and PQS operation at a wavelength of 1.3??m.

Single frequency MOPA based on Nd:YAG single crystal fiber and rods

We demonstrate a single frequency 1064 nm master oscillator power amplifier (MOPA) system operating in macro-micro pulse scheme. The repetition rate for the macro pulses was 300 Hz with pulse duration of 300 μs. Micro pulses operated at 25 kHz. The master laser was a single-longitudinal-mode electro-optically Q-switched Nd:YAG laser with an output power of 250 mW and pulse duration of 33 ns. Three stages of power amplifiers based on Nd:YAG single crystal fiber and rods were designed. The final output power reached 31.3 W with pulse duration of 30 ns and linewidth of less than 130 MHz. Micro pulse energy of 13.9 mJ was obtained with a peak power of up to 464 kW. The beam quality factors (M2) were measured to be 1.56 and 1.76 in horizontal and vertical directions, respectively.

High power broadband LiF:F 2 - color center laser

A high power LiF:F(2)(-) color center laser is demonstrated with broadband emission. The excitation source is a quasi-continuous wave diode side-pumped acousto-optically Q-switched Nd:YAG laser. Under an incident 1064-nm laser power of 25.4 W, the highest output power of up to 4.7 W is obtained with a macro pulse repetition rate of 400 Hz and a micro pulse repetition rate of 50 kHz. The broadband emission is centered at 1142 nm with a bandwidth of 13 nm.

Diode pumped CW and passively Q-switched Nd:LGGG laser at 1062 nm

We report a Nd:LGGG laser at 1062 nm in the operations of the continuous-wave (CW) and passively Q-switching. The maximum CW output power of 5.62 W was obtained, corresponding to an optical-to-optical conversion efficiency of 49.0% and slope efficiency of 55.9%. By using Cr4+:YAG with initial transmission of 94% as the saturable absorber, for the first time, we got the maximum passively Q-switched output power of 1.21 W, accompanied with a highest pulse repetition rate of 27.1 kHz and a shortest pulse width of 9.1 ns.