全光纤级联拉曼光纤激光器及其泵浦源实验研究

【作者】 余飞；

【导师】 周晓军；

【作者基本信息】 电子科技大学 ， 光学工程， 2008， 硕士

【摘要】 拉曼光纤激光器是一种基于受激拉曼散射效应的光纤激光器,只要具有合适波长的泵浦源和反馈元件,拉曼光纤激光器可以获得任意波长的激光输出。级联拉曼光纤激光器具有增益介质长、噪声低、调谐范围宽、可同时实现多波长输出和与光纤耦合效率高等优点。级联拉曼光纤激光器用于泵浦光纤拉曼放大器可以在很宽的带宽内实现平坦放大,是光纤拉曼放大器理想的泵浦源。多波长输出的级联拉曼光纤激光器用作光纤通信系统,特别是波分复用系统的信号源,可以减少发射端的激光器数量。本文首先对受激拉曼散射的原理进行了介。然后设计了一个五级级联拉曼光纤激光器系统,包括级联拉曼光纤激光器谐振腔的设计、泵浦源的设计和用于泵浦掺镱光纤激光器的大功率半导体激光器驱动电路的设计,在实验室对所设计系统的各部分特性进行了测试,并对实验结果进行了分析。本论文的主要研究内容如下:(1)对受激拉曼散射的基本原理以及国内在拉曼光纤激光器和掺镱双包层光纤激光器上的研究进展作了介绍。(2)对掺镱石英光纤中镱离子的受激辐射进行了介绍,完成了级联拉曼光纤激光器用大功率泵浦源――掺镱双包层光纤激光器的设计制作。(3)对掺镱双包层光纤激光器的泵浦源――半导体激光器的特性进行了介绍,完成了大功率半导体激光器驱动电路的设计。(4)对Bragg光纤光栅进行了介绍,完成对所使用光纤光栅的实验测试。(5)设计了一个基于线性腔结构的五级级联拉曼光纤激光器,对所设计的激光器进行了测试,并对测试结果进行了分析。(6)对设计的掺镱双包层光纤激光器及大功率半导体激光器的驱动电路进行了测试。测试结果显示,所设计的大功率半导体激光器驱动电路稳定可靠,满足使用要求,级联拉曼光纤激光器第五阶Stokes光的最大输出功率为599mW。文中还对造成级联拉曼光纤激光器泵浦阈值高、光-光转换效率以及斜率效率低的原因进行了分析。更多还原

【Abstract】 Raman fiber lasers （RFL） which base on the stimulated Raman scattering （SRS） effect, can generate any wavelengths output if it is pumped with an appropriate pump source and feedback elements. Cascaded Raman fiber lasers （CRFLs） have some advantages, such as longer gain medium, lower noise, broader turning, multi-wavelengths output and high coupling efficiency. The CRFLs, used as pump source in Raman fiber amplifier, can generate flat gain in a wide-band range. It is an ideal pump resource of Raman fiber amplifier. Multi-wavelengths CRFLs can be used as light source in fiber communication system, especially in WDM system. With it, the number of lasers in transmitter will be decreased.In this dissertation, SRS theory is introduced firstly. Then, a five-order CRFL is designed, including the design of CRFL resonant cavity, pump source, and the driving circuit of high power LD,which used as pump source for Yb³⁺-doped double claded fiber lasers （DCFLs）. The characteristics of each part of the system are measured in laboratory and the experimental results are analyzed.The main contents of this dissertation are as followings:（1） The basic theory of SRS, the domestic and abroad research state for RFLs and Yb³⁺-doped DCFLs are introduced.（2） The transition processses between the energy states of the Yb³⁺ in Yb-doped fiber are presented. The high power DCFL, used as pump source for CRFL, is designed.（3） The drive circuit for high power LD, which used for pump DCFL is designed. The characteristics of LD are also introduced in this dissertation.（4） Bragg fiber grating is brifly introduced, and transmitiom spectra of the fiber gratings we used are experimentally measured.（5） The resonance cavity of a five-order CRFL in line style is designed. The CRFL is testd in the laboratory, and the experimental results are analysed.（6） The DCFL and the drive circuit for LD are mesured.The test results show that the driving circuit designed for high power LD is stable and fulfilled the requirement. The fifths Stokes light maximum output of the CRFL is 599mW. Reasons for high pump threshold, low light-light conversion efficiency and low slope efficiency of the CRFL are also analyzed in the dissertation.更多还原