Shen De-zhong

Intracavity-doubled self-Q-switched Nd,Cr : YAG 946/473 nm microchip laser

We carried out the operation of an intracavity frequency-doubled self-Q-switched Nd, Cr: YAG/KNbO3 946/473 nm microchip laser pumped by a Ti:sapphire laser. The overall cavity length was about 4 mm. The maximum average blue power of 12 mW was achieved with a repetition rate of 13 kHz at an absorbed pump power of 545 m W. The pulses of the 4 73 nm laser had a duration of 7 ns and a peak power of 132 W at this pump level. The conversion efficiency was 2.2% with respect to the absorbed pump power of a 808 nm laser.

Synthesis and Crystal Structure of Yb-doped S-FAP

To abtain large crystals for improving the physical and optical properties of materials, the crystal of Yb-doped S-FAP was sythesized by the Czochralski method, the growth process was analyzed, and its structure was determined. This material was confirmed to have a hexagonal structure, unit-cell parameters (a=b=0.9683(4) nm, c=0.7277(4) nm) are slightly different from the crystal parameters of S-FAP reported before.

Properties of a New Nonlinear Optical Crystal CdZn2B2O6

Cadmium dizinc diborate (CdZn2B2O6) single crystals have been grown for the first time. The crystal structure of CdZn2B2O6 is the same as that of the Cd3Zn3B4O12. The x-ray diffraction, infrared and Raman spectra, differential scanning calorimetry analysis and density indicate that the physical and chemical properties of both crystals are very similar. Especially, the nonlinear optical coefficients of CdZn2B2O6 and Cd3Zn3B4O12 crystals are 2.6 and 2.4 times as large as that of KH2PO4 crystal respectively. Chemical etching experiments indicated that these crystals are very stable in neutral solution and not hygroscopic in air at room temperature.

Improvement of the Two-Beam Coupling Response Time in Photorefractive Double-Doping KNbO3

We report experimental studies on the photorefractive response of KNbO3 doubly doped with manganese and rubidium, iron and rubidium, respectively. Two-beam coupling response time in KNbO3:Mn:Rb is 3 to 10 times shorter while the two-beam coupling gain coefficient remains almost the same when compare with that in KNbO3:Mn. On the other hand, under similar conditions, two-beam coupling response time in KNbO3:Fe:Rb is 6 times faster than that in KNbO3:Fe.

KNbO3: Fe Optical Frequency Discriminator

By using the feature that KNbO3: Fe has fast response time, we demonstrate a KNbO3: Fe optical frequency discriminator (KOFD) which is based on the method of time-delayed laser-induced double gratings. This KOFD can be used to measure the frequency difference between two laser fields.