【作者】 吴俊芳；

【导师】 陈培锋；

【作者基本信息】 华中科技大学 ， 物理电子学， 2004， 硕士

【摘要】 双包层光纤激光器目前可谓是光纤激光器家族的佼佼者,它使用包层泵浦技术使光纤激光器摆脱了小功率器件的地位,把输出光束的大功率、高质量,和光纤激光器的一切优点集于一身,又因其光纤形式可以方便的用在光通信领域,所以不断受到人们的关注。本文研究以二极管激光器做泵浦源,以掺Yb3+的双包层光纤为增益介质,采用F-P腔型的光纤激光器。本文所做的理论和实验方面的研究主要有以下几个方面:(1)在广泛查阅国内外文献的基础上,对国内外光纤激光器领域内的研究现状和发展方向进行了综述,介绍了本课题研究的现实意义。(2)介绍了光纤激光器的基本理论;描述了Yb3+的能级结构和光谱特性,显示出它做为光纤掺杂离子的优越性;双包层光纤结构和包层泵浦技术相结合,为光纤激光器的大功率奠定了基础。(3)从分析高斯光束的变换入手,推导出高斯光束在光纤间耦合时,参数选择的一般规律,并针对本文在实际研究中遇到的特定情况,设计了一套耦合系统,指导了实验的开展。(4)对自行设计、制作的掺Yb3+双包层光纤激光器进行了实验研究。观察了激光产生前后的实验现象,从输出纵模、输出功率、斜率效率等几方面对激光器进行了详细分析。还特别注意到了光纤激光器的可饱和效应,并做出了合理解释。分析了实验中存在的问题,提出了今后工作的几点改进意见。更多还原

【Abstract】 Double-clad fiber laser can be honoured as one of the twinkling stars in fiber laser family. The clad-pumping technology helped fiber laser shake off the impression of low-power. Double-clad fiber laser syncretize the high-power and high-quality of laser beam and all of the virtues of fiber laser. In addition, it can be easily applied in optic-communications. So it draws more and more attentions. The thesis details the experiment of the Yb3+-doped double-clad fiber laser, which is pumped by Laser Diodes and works in a F-P cavity. The main theoretical and experimental researches are included in this thesis:(1) The state of the researches and the development way in the field of fiber laser worldwide are summarized based on comprehensive references reading, and the practical significance of this research subject is introduced.(2) The basic theory of fiber laser is introduced; The energy level and spectrum characteristics of Yb3+ are detailed, which indicate its superiority to emit laser; The combination of double-clad fiber and clad-pumping technology paves the way to high-power for fiber.(3) After analyze the changing of Gaussian beam, it is studied that the coupling of Gaussian beam between fibers. The general law in deciding the parameters of coupling system is deduced. A special coupling system is designed accordingly to couple LDs into the Yb3+-doped fiber.(4) The experiment of Yb3+-doped double-clad fiber laser is carried out. The process of laser naissance is observed, and several output characteristics of the laser, including longitudinal mode, power and slope efficiency are analyzed at large. The phenomenon of saturable absorber is explained. There are some problems in the experiments, then some improvement suggestions are presented.更多还原