单纵模激光器及自拍频稳频实验研究物理电子学专业论文.docxVIP

哈尔滨工业大学工学硕士学位论文 哈尔滨工业大学工学硕士学位论文 - - II - Abstract Single longitudinal mode laser has good characteristics such as coherence and monochromaticity. Therefore, it is widely used in accurate measurement, optical communication, optical frequency scale, high resolution spectroscopy. The laser frequency is affected by its surroundings, usually being a fluctuating signal as a variable of time. Frequency stabilization technique is required in order to stabilize laser frequency. Frequency discrimination system is a part of frequency stabilization system. We can use it to discriminate laser frequency, and get the frequency discrimination curve which is used by servo control system to stabilize laser frequency as control signal. The quality of the frequency discrimination system largely influences frequency stabilization. The greater the slope of the frequency discrimination curve, the better the frequency stabilizing system works. So the frequency discrimination system is very important to the frequency stability of the laser This dissertation introduces the methods of several frequency discrimination technology and these fundamentals and characteristic. Then, we choose the self- heterodyne as laser frequency discrimination system and design the fiber delayed system. We analyze the influence to the DPL and optimize parameters of the laser that makes it more stabilization of frequency. In the experiment aspect, a single longitudinal mode laser using twisted mode technology is set up and configured. Near threshold, we got mostly 100% single longitudinal mode output. We study how parameters such as input power, cavity length and output mirror transmissivity impact to the relaxation oscillation, then makes it disappear with passive Q-switch technique and analyze the output characteristic. We prove the output laser as single longitudinal mode output with F-P etalon. Then we do beating experiment with self-produced SLM and stable frequency fiber laser, measure th