Zhu Xiaolei

Kilohertz Electro-Optic Q-Switched Nd:YAG Ceramic Laser

We investigate the lasing characteristics of a laser-diode-array side-pumped electro-optic Q-switched Nd:Y3Al5O12 ceramic laser operating at 1000 Hz pulse repetition rate. Using a YAG polycrystalline rod with Nd3+ concentration of 1 at.% as the gain medium, pumping with 808 nm laser-diode-arrays, the Q-switched laser output at 1064 nm wavelength with 23 mJ pulse energy and less than 12 ns FWHM pulse width are obtained at a pumping power of about 400 W, the slope efficiency is around 15%, the output beam divergence angle is about 1.2 mrad.

Novel Optical Parametric Amplifier at 1572 nm Wavelength Using KTP Crystal

A novel master oscillator/power amplifier architecture for optical parametric conversion of high pulse energy from 1.064 μm to 1.572 μm in KTiOPO4 crystal is presented. A high gain of more than 80 at 1.572 μm pumped by a high energy Q-switched pulse laser is realized. With a seeding signal energy of 1 mJ, and 400 mJ pump pulse at 100 Hz, an amplified signal pulse energy of over 80 mJ is obtained. The total optical-optical conversion efficiency reaches 21%.

High-Efficient Nd:YLF Q-Switched Laser Operating at 523.5 nm

An intracavity frequency doubling electro-optically Q-switched Nd:YLF 523.5 nm laser is developed. An appropriate cylindrical lens is employed in the oscillator to optimize the mode size and to improve the stability of the cavity. With an incident pump pulse energy of 58 mJ at a 500 Hz repetition rate, a green pulse energy of 16.8 mJ at 523.5 nm is obtained, corresponding to an optical-optical conversion efficiency of 29%. The pulse width is less than 8 ns, and the beam quality factor is M2 ≤ 2.5.

A 5.9-mJ 500-Hz Electro-Optic Q-Switched 1053 nm Nd:LiLuF4 Laser

An efficient and high power 1053 nm electro-optic Q-switched Nd:LiLuF4 laser, end-pumped by two fiber coupled laser diodes at wavelength 806 nm, is reported for the first time. With an incident pump power of 24.4 W, the maximum laser output power of 7.3 W is achieved in free-running mode, and the optical conversion efficiency is 29.8%. For the Q-switched operation, the shortest pulse width of 17 ns is obtained at the pulse repetition rate of 500 Hz, corresponding to the pulse energy of 5.9 mJ with the peak power of 0.35 MW.

A Compact Diode-Pumped Injection Seeded Nd:YAG Laser with Resonance-Detection Technique

A diode pumped injection seeded single-longitudinal-mode (SLM) Nd:YAG laser is achieved by using the resonance-detection technique in Q-switching operation. The pulsed oscillator laser uses a folded cavity to achieve compact construction. This system operates at 100?Hz and provides over 20?mJ/pulse of single-frequency 1064?nm output. The M2 values of horizontal and vertical axes are 1.58 and 1.41, respectively. The probability of putting out single-longitudinal-mode pulses is 100%. The 355?nm laser output produced by frequency tripling has a linewidth less than 200?MHz. The laser can run over eight hours continually without mode hopping.