Shishu Cheng

Crystal growth, spectroscopic and laser properties of Tm:LuAG crystal

Tm:Lu3Al5O12 (Tm:LuAG) crystal was grown by the Czochralski method. The segregation coefficient was measured by Inductively Coupled Plasma Atomic Emission Spectrometer. The cell parameters were analyzed with X-ray powder diffraction experiments. The absorption and fluorescence spectra of Tm:LuAG crystal at room temperature were investigated. With a 20 W fiber-coupled diode laser as pump source, the continuous-wave (CW) laser action of Tm:LuAG crystal was demonstrated. The maximum output power at 2020 nm was obtained to be 3.04 W, and the slope efficiency was 25.3%.

Spectral characterization and laser performance of a mixed crystal Nd:(Lu x Y 1-x ) 3 Al 5 O 12

An Nd-doped Lu(1.5)Y(1.5)Al(5)O(12) (Nd:LuYAG) crystal was obtained by Czochralski method. Absorption and emission spectra were recorded at low and room temperature. Continuous wave (CW) and passively Q-switched laser operations of Nd:LuYAG crystal were, to our knowledge, demonstrated for the first time. A CW output power of 1.67 W with slope efficiency of 39.8% was obtained. In the passively Q-switched operation, the shortest pulse width, largest pulse energy, and highest peak power were achieved to be 9.6 ns, 61.7µJ, and 6.4 kW, respectively, with Cr(4+):YAG crystals as the saturable absorbers.

Crystal growth, spectral and laser properties of Yb3+:NaGd(WO4)(2) crystal

Yb3+-doped NaGd(WO4)2 (Yb:NGW) crystal has been successfully grown by Czochralski method. The rocking curves from (400) plane of as-grown Yb:NGW crystal was measured and the full-width values at half-maximum was 21″. The polarized absorption spectra, the fluorescence spectra and the fluorescence decay lifetime of Yb:NGW crystal were measured at room temperature. The spectroscopic parameters of Yb:NGW crystal are calculated and compared, with those of Yb:YAG crystal. A continuous wave output power of 3.01 W at 1048 nm was obtained with a slope efficiency of 71% by use of diode pumping.

Crystal growth, spectroscopic and CW laser properties of Nd0.03Lu2.871Gd0.099Al5O12 crystal

Nd0.03Lu2.871Gd0.099Al5O12 (Nd:LuGdAG) crystal was grown by the Czochralski method. The absorption, fluorescence spectra and fluorescence lifetime of Nd:LuGdAG crystal at room temperature were investigated for the first time. We reported the continuous-wave (CW) Nd:LuGdAG laser operation under diode pumping. Output power of 1.43 W at 1064 nm was achieved with a slope efficiency of 34.1%. All the results show that Nd:LuGdAG crystal is a promising laser material.

Spectroscopic analysis and lasing of Er:Lu 1.5 Y 1.5 Al 5 O 12 crystals

A high optical quality erbium-doped LuYAG single crystal has been grown by the Czochralski technique. The segregation coefficient of Er3+ was measured to be 1.05. The absorption and emission spectra were measured at room temperature. The spectroscopic parameters were calculated using the Judd–Ofelt (J-O) theory, and the J-O parameters Ωt (t=2, 4, 6) were found to be 0.89×10−20, 1.64×10−20, 1.23×10−20 cm2, respectively. The emission cross section of the Er3+ 4I13/2→4I15/2 transition were calculated by the Fuchtbauer–Ladenburg formula, and the room-temperature fluorescence lifetime of the Er3+ 4I13/2→4I15/2 transition was measured to be 9.9 ms. Finally, promising laser performance with Er:Yb fiber laser pumping is described.