Studies on Nonlinear Physics and Application Technology of Thin-Slice Solid-State Lasers with Coated End Mirrors

通过对激光二极管（LD）泵浦薄层固体激光器非线性物理和应用技术的研究，得到了以下主要结果：(1)系统地研究了反射端表面粗糙度和抽运光束光斑尺寸对大孔径LD抽运薄薄固体激光器激光图案形成的影响。实验中发现了量子台球模式、复合晶格模式和散斑模式等奇特的激光模式。(2)在常规钕中发现了局部横模的分离和伴随的包括混沌在内的高速强度调制。：平均晶粒尺寸为几十微米的YAG陶瓷激光器。这些现象在理论上得到了很好的再现。(3)采用以下方法解决了陶瓷激光器固有的问题：(1)选择激励直径足够大的inces - gaussian激光模式，并使其晶粒尺寸足够大；（二）使用平均晶粒尺寸为几微米的微晶陶瓷激光器。在这两种情况下，都实现了稳定的振荡而不分离到局部模态。(4)开发了微芯片固体激光器高阶inces - gaussian模式控制代的抽运方法，实现了对小粒子运动的操纵，形成了各种类型的新型光学旋涡。(1)通过改进移频反馈方案中的器件，光学灵敏度提高了两个数量级。(2)实现了80-500mn粒径范围内浓度低于1ppm的水中小颗粒的实时振幅为1nm的振动测量和快速定色。利用所研制的载波复用方法，实现了1纳米幅值的三维实时振动测量。调频解调电路在fa-A时间内捕获了布朗粒子的整体动力学。(3)将自混合激光测量技术应用于流动测量，成功实现了流速和动态粘度的快速测量。对262-nmpolystyrene乳胶球在0.01ppm的浓度限值下进行了流动中小颗粒的检测。少

The following main results have been obtained through studies on nonlinear physics and application technology using laserdiode (LD) pumped thin-slice solid-state lasers.1. Pattern formations in LD-pumped thin-slice solid-state lasers(1) Effects of surface roughness of reflective ends and pump-beam spot size on lasing pattern formations were studied systematically in wide-aperture thin-slim solid-state lasers with LD pumping. Such curious lasing patterns as quantum billiard-like modes, composite lattice modes and speckle modes were found experimentally.(2) Segregations into local transverse modes' and associated high-speed intensity modulations inclnding chaos were found in conventional Nd. : YAG ceramic lasers whose average grain size is several tens of microns. These phenomena were well reproduced theoretically.(3)The inherent problem in ceramic lasers was solved in the following way (i) The selective excitation of Ince-Gaussian lasing modes with learn diameters sufficiently larger th … More an grain sizes ; (ii) The use of micro-grained ceramic lasers with average grain size of few microns. In both cases, stable oscillations without segregations into local modes were realized.(4)The Lapumping method for controlled generations of higher order Ince-Gaussian modes in microchip solid-state lasers was developed and formation of various types of novel optical vortices was realized toward manipulating motions of small paricles.2.LD-pumecl self-mixing thin-slice solid-state laser metrology(1) We increased the optical sensitivity by two-orders of magnitude by improving devices in the frequency-shift feedback scheme.(2) We realized real-time vibrometry of 1-nm amplitude and quick sizing of small particles in water whose concentration is below 1 ppm in the particle diameter range of 80-500mn. The three-dimensional real-time vibrometry of 1-nm-amplitude was realized by usinghe carrierfrequency multiplexing method which we developed. The overall dynamics of Brownian particles was captured for the fa-A time by the FM demodulation circuit.(3) We applied our self-mixing laser metrology to flow measurements and quick measurements of flow velocity and dynamic viscosity were successfully demonstrated. Also, the detection of small particles in the flow was done under the concentration limit of 0.01ppm for 262-nmpolystyrene latex spheres. Less