高效率,窄脉冲1198.5nm Ba(NO_3)_2喇曼激光器(英文)

利用1 064 nm的Nd∶YAG激光抽运振荡腔内的硝酸钡晶体,获得高效率、窄脉冲的喇曼激光输出.硝酸钡晶体由水溶液降温法生长,长度为48 mm.喇曼振荡腔由对抽运光、一阶、二阶斯托克斯光有不同反射率的双色平面镜构成.当抽运光功率达到4.5 W时,获得最高的一阶斯托克斯喇曼激光功率为1.48 W,相应的转换效率为32.9%,并测得斜率效率为40%.由于受激喇曼散射的作用,喇曼脉冲光由抽运脉冲光的19.8 ns压缩为2.4 ns,获得的喇曼激光脉冲波形具有的＂上升沿陡峭、下降沿缓慢＂的特性,对其形成过程作了

A high-efficiency, short-pulse 1198.5 nm Raman laser was demonstrated by using stimulated Raman scattering (SRS) in the barium nitrate (Ba(NO₃)₂) crystal which was pumped by a 1064 nm Nd : YAG laser. With an incident pump power of 4.5 W, a maximum of 1.48 W Raman output power at a repetition rate of 30 Hz was obtained, corresponding to an overall optical-to-optical conversion efficiency of 32.9%. The slope efficiency was calculated as 40%. The pulse width of the Raman pulses was reduced to 2.4 ns compared to the pump pulse width of 19.3 ns. The typical Raman pulse had an asymmetric shape, with a very steep positive-going slope and an extended negative-going slope, the mechanism of which was also demonstrated with qualitative analysis. The wavelength of the Raman laser (the first Stokes) was measured to be 1198.5 nm with FWHM of 1.2 nm.}