Opt Lett. 2018 Aug 15;43(16):3973-3976. doi: 10.1364/OL.43.003973.
Characteristics of intensity noise of optically pumped vertical-cavity surface-emitting lasers and solid-state lasers, induced by the beating of the main lasing mode and non-lasing side modes and its reduction, have been reported in recent years. The mode beating noise of an external cavity diode laser composed of an electrically pumped edge-emitting laser diode chip is studied experimentally in this Letter. The noises due to the beating of the main mode with the first- to third-order side modes are observed, and multiple sub-peaks in the beating noise are measured. It is assumed that the new phenomena are coming from the enhanced four-wave mixing in the longer-active medium. Intensity noise reduction is also demonstrated by using the second harmonic generation of a beta barium borate crystal as a nonlinear absorber.
近年来，人们报道了受主激光模和非激光边模拍频影响的光泵浦垂直腔面发射激光器和固体激光器强度噪声的特性，并对其进行了抑制。本文实验研究了由电泵浦边发射激光二极管芯片构成的外腔半导体激光器的模式拍频噪声。观察到了主模与第一到第三阶边模拍频引起的噪声，并测量了拍频噪声中的多个次峰。我们认为这些新现象来自于较长激活介质中增强的四波混频。还通过使用β硼酸钡晶体的二次谐波产生作为非线性吸收器，实现了强度噪声的降低。
