Anisotropic stimulated emission cross-section measurement in Nd: YVO4
Rui Guo(郭瑞)1, Yijie Shen(申艺杰)1, Yuan Meng(孟鸢)1, Mali Gong(巩马理)1,2
1 Department of Precision Instrument, State Key Laboratory of Precision Measurement and Instruments, Tsinghua University, Beijing 100084, China;
2 Department of Precision Instrument, State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
As a crucial parameter in the design and analysis of laser performances, stimulated emission (SE) cross-section is currently considered to be dependent on several factors, such as temperatures and eigen-polarizations for anisotropic crystals. In contrast with these factors, impact of propagating directions upon SE cross-section has garnered less attention. In this paper, to investigate the SE cross-section in arbitrary propagating directions, fluorescence spectra for the transition 4F3/2→4I11/2 in Nd:YVO4 are measured in different propagating directions. Based on Fuchtbauer-Ladenburg equation model, the propagating direction-dependent SE cross-section spectra in Nd:YVO4 are obtained for the first time, to our best knowledge. A novel concept of anisotropic SE cross-section is proposed to interpret the propagating direction-dependent effect. The experiment results reveal that for an arbitrary propagating direction the SE cross-section of e light around 1064 nm can be expressed as a superposition from two principle axial propagating directions with a weight of plane projection.
Magneto–optical trap for neutral mercury atoms Liu Hong-Li (刘洪力), Yin Shi-Qi (尹士奇), Liu Kang-Kang (刘亢亢), Qian Jun (钱军), Xu Zhen (徐震), Hong Tao (洪涛), Wang Yu-Zhu (王育竹). Chin. Phys. B, 2013, 22(4): 043701.
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