【作者】 葛剑虹；

【导师】 陈军；

【作者基本信息】 浙江大学 ， 光学工程， 2003， 博士

【摘要】 本文对半导体激光器输出激光的模式特性、振荡特性以及外腔反馈注入半导体激光器改善其模式特性的技术开展了一系列的研究工作，建立了一套实用有效的外腔反馈注入振荡系统，并对两种不同类型的半导体激光器（半导体激光器列阵和宽接触条形半导体激光器）进行了实验研究和理论分析，成功获得了窄线宽单瓣近衍射极限的激光输出。 文中提出了一个结构简单，输出稳定，腔内器件失调不灵敏的半导体激光器外腔反馈一次注入系统，并用光线传输矩阵对该外腔的特性进行了详细的理论分析。在半导体激光器列阵的外腔实验研究中，获得远场分布光瓣宽度（FWHM）为0.46°，相应于光束质量为1.12倍衍射极限的激光输出。 在宽接触条形半导体激光器的外腔实验研究中，设计了一个新颖的外腔结构，即通过外腔使得注入激光在腔内多次往返放大，获得远场分布光瓣宽度（FWHM）为0.53°，相应于光束质量为1.3倍衍射极限，功率为320mW单瓣近衍射极限的激光输出。 在前腔镜对增透膜的宽接触条形半导体激光器的外腔实验研究中，在上述的外腔结构中加入标准具，利用光栅和标准具共同的选模作用，获得光瓣宽度（FWHM）为0.44°，相应于光束质量为1.08倍衍射极限，谱宽为0.02nm（10GHz），功率为140mW的单模输出。 本文通过超模理论和宽接触模式理论对折射率导引、增益导引半导体激光器列阵和宽接触条形半导体激光器输出激光的空间模式特性进行了研究。并在此基础上，理论分析了外腔反馈注入改善半导体激光器输出激光模式特性的机理，同时还讨论了外腔反馈注入对半导体激光器输出激光的功率，出光阈值，振荡频率等特性的影响，得出了和实验结果相吻合的结论。 本文理论研究了LD泵浦自调Q微片激光器的输出特性，并进行了半导体激光器泵浦Cr⁴⁺，Nd³⁺：YAG微片和微柱晶体自调Q激光器两部分实验研究，在连续和脉冲泵浦状态下均获得了高重复频率，窄脉宽的自调Q激光脉冲输出，并且首次采用加基电流的矩形脉冲预泵浦方法，获得了可控而且稳定的单脉冲输出。更多还原

【Abstract】 The model characteristics and oscillation characteristics of a semiconductor laser are analyzed in detail. Beam quality improvement of different kinds of semiconductor lasers include laser diode array and broad area laser diode with external cavity feedback are studied and single-lobed far-field patterns with single longitudinal mode laser output is achieved.In the dissertation, a simple- external cavity geometry that has good mode discrimination and insensitivity misalignment of the cavity elements is analyzed in detail with ray transfer matrices and investigated on a laser diode array. With this kind of setup, a laser beam with 0.46?far field divergence angle, which corresponding to 1.12 times the diffraction limit is obtained.Another novel external cavity geometry through which the feedback laser beam can oscillate in the external cavity is studied on the broad area laser diode. With this kind of setup, a laser beam with 320mW output power, 0.53?far field divergence angle, which corresponding to 1.3 times the diffraction limit is obtained.Improvement the external cavity geometry with FP etlon, with the longitudinal mode selection of grating and FP etalon, a laser beam with 140mW output power, 0.44?far field divergence angle, which corresponding to 1.08 times the diffraction limit, spectral line width of 0.02nm (10 GHz) is obtained.The optical characteristic of the index-guide, gain-guide laser diode array and the broad area laser diode is calculated using supermode theory and broad-area mode theory. Also, based on the broad-area mode theory, the mode characteristic of external cavity semiconductors is studied. The dependence of output power, threshold and oscillation frequency on external cavity are presented and compared with experiment result.Laser diode pumped Gr4+, Nd3+:YAG self Q-switched laser is also studied in the dissertation. Under the condition of the CW pumping and pulsed pumping, high repetition rate, narrow pulse width laser beam are all obtained. In order to stabilize the single pulse output, pre-pumping technology with the rectangular pulsed pump electric current on the certain pre-current is used on laser diode. The stabilizing efficiency was very significant.更多还原