Cong Zhenhua

Modelling of passively Q-switched lasers with intracavity Raman conversion

We present a model of passively Q-switched Raman lasers by utilizing the rate equations. The intracavity fundamental photon density, Raman photon density and the initial population-inversion density of the gain medium are assumed to be of Gaussian spatial distributions. These rate equations are normalized by introducing some synthetic parameters and solved numerically, and a group of general curves are generated. From these curves we can understand the dependence of the Raman laser pulse characteristics on the parameters about the pumping, the gain medium, the Raman medium and the resonator. An illustrative calculation for a passively Q-switched Nd3+:GdVO4 self-Raman laser is presented to demonstrate the usage of the curves and related formulas.

Efficient Diode-End-Pumped Actively Q-Switched Nd:YLF/SrWO 4 Raman Laser

An efficient diode-end-pumped actively Q-switched Nd:YLF/SrWO4 Raman laser is demonstrated. The fundamental wave is 1047.0 nm and the corresponding first-Stocks wave is 1158.7 nm. With a pumping power of 10.5 W, the average output power of 2.2 W at 1158.7 nm is obtained, with the corresponding optical conversion efficiency of 20.9%. At a repetition rate of 6 kHz, the pulse width of the Raman laser is 8.7 ns and the peak power is calculated to be 42.1 kW. The beam quality factors M2 in horizontal and vertical directions are 1.3 and 1.5, respectively.

Diode-pumped Passively Q-switched Nd:YAG/BaWO4/KTP Yellow Laser

A diode-pumped passively Q-switched Nd:YAG/BaWO4/KTP yellow laser is presented for the first time. The obtained maximum average output power, conversion efficiency, pulse energy were 1.21 W, 9.06%, and 68.5 μJ, respectively.