Zhenfang Peng

Long distance, distributed gas sensing based on micro-nano fiber evanescent wave quartz-enhanced photoacoustic spectroscopy

A long distance, distributed gas sensing using the micro-nano fiber evanescent wave (FEW) quartz enhanced photoacoustic spectroscopy technique was demonstrated. Such a sensor scheme has the advantages of higher detection sensitivity, distributed gas sensing ability, lower cost, and a simpler fabrication procedure compared to conventional FEW gas sensors using a photonic crystal fiber or a tapered fiber with chemical sputtering. A 3u2009km single mode fiber with multiple tapers and an erbium doped fiber amplifier with an output optical power of 700 mW were employed to perform long distance, distributed gas measurements.

Diode-pumped continuous-wave and passively Q-switched Nd:GdLaNbO 4 laser

A diode-pumped passively Q-switched 1065 nm laser with a novel Nd:Gd0.89La0.1NbO4 mixed crystal was demonstrated for the first time to the best of our knowledge. First, the crystal characteristics were investigated. In the continuous-wave (CW) operation, when the absorbed pump power was 12.24 W, the maximum CW output power of 3.06 W was obtained with the optimum transmission (20%) of the output plane coupler. In the passively Q-switched situation, when Cr4+:YAG crystal with an initial transmission of 90% served as the Q-switched saturable absorber, the maximum repetition rate, pulse peak power and minimum pulse width were 24.5 kHz, 1.13 kW and 32 ns, respectively, at the absorbed pump power of 12.24 W.

Doubly Q-switched tape casting YAG/Nd:YAG/YAG ceramic laser

Abstract A doubly Q-switched 1.06 μm pulsed laser using a novel tape casting YAG/Nd:YAG/YAG composite ceramic with a sandwich structure was demonstrated for the first time. Compared to purely acousto-optical (AO) Q-switching, this laser using an AO Q-switch and Cr4+:YAG saturable absorber simultaneously can generate shorter pulses. The pulsed laser performance was investigated at two modulated repetition rates of 10 and 20 kHz.