雙波長自鎖膜Nd:YAG雷射之研究

Abstract

本論文在闡述雙波長自鎖模Nd:YAG雷射之相關研究。首先，我們利用特殊鍍膜的輸出鏡，設計一短腔長雙波長自鎖膜Nd:YAG雷射。藉由改變腔內耗損，我們可以在實驗中獲得1064nm和1123nm以及1064和1123nm同時輸出的雙波長鎖膜雷射。在此雙波長鎖膜雷射的操作下，我們可以在單發4.5GHz的鎖膜脈衝中觀察到14.7THz的光拍頻脈衝序列。再者我們利用單晶的Nd:YAG晶體，產生正交偏振自鎖膜雷射，拍頻現象可以在兩正交偏振被量測，我們發現此拍頻現象會隨應力改變呈線性變化，變化範圍從MHz到GHz，最高可達1.48GHz。

The aim of this thesis is focused on the two different method to achieve dual-wavelength self-mode-locked Nd:YAG lasers. First of all, we utilize a specific coated output coupler to realize a dual-wavelength self-mode-locked Nd:YAG laser in a short cavity. In the experiment, the dual wavelength at 1064 and 1123 nm can be stably emitted by modulated the cavity losses. A train of ultrashort pulses with a repetition rate up to 14.7 THz can be observed in a mode-locked pulse owing to the optical beating. In the second experiment, we use the monolithic Nd:YAG lasers to generate two orthogonally polarized mode-locked components. The beat frequency between two orthogonally polarized mode-locked components is observed. It is found that the beat frequency increases linearly with increasing the applied stress. The beating frequency range from MHz to several GHz, highest to 1.48GHz.