利用飽和吸收鏡(SBR)作為被動元件，我們觀察到了外腔半導體雷射混成式鎖模的現象，且分別對飽和吸收鏡做砷離子佈值前後的行為作進一步探討。同時，為了要比較被動元件所產生的效應，我們利用相同的腔，將飽和吸收鏡以銀鏡取代形成主動鎖模。在使用經離子佈值的飽和吸收鏡的系統下，可得到最短脈寬15.6皮秒，尖峰功率為2.4瓦；光譜半高寬為3.4奈米，所對應的時間-頻寬乘積為22.6。若能使脈衝再經色散補償或對飽和吸收鏡做更適當的設計，必能獲得更短的脈衝。

Hybrid mode locking behavior is observed in an external cavity semiconductor laser with as grown and arsenic-ion-implanted Saturable Bragg Reflectors (SBR). For comparison, active mode locking in the same cavity but a silver mirror replacing the SBR was also investigated. Pulse width as short as 15.6 psec with a peak power of 2.4 W was obtained with the implanted SBR. The spectral bandwidth is 3.4 nm. The corresponding time-bandwidth product is 22.6. Still shorter pulses should be possible with intra-cavity dispersion compression and optimum design of the SBR.

Chapter I Introduction
1.1 Introduction
1.2 Introduction of hybrid mode locking pulse lasers
1.3 Motivation
1.4 Outline
Chapter II Mode Locking of Lasers : Basic Principles and Mode Locking Mechanisms
2.1 Gain coefficient of a slow saturable absorber laser cavity
2.2 Gain coefficient in a passive mode locking semiconductor laser cavity
2.3 Active mode locking
2.4 Active mode locking of a semiconductor laser in an external cavity
2.5 Passive fast saturable absorber mode locking
2.6 Slow saturable absorber mode locking
2.7 Passive mode locking in semiconductor laser structures
2.8 Saturable Bragg Reflector
2.9 SBR carrier lifetime reducing and measurement
Chapter III Experimental Methods
3.1 Laser configuration
3.2 Diagnostic techniques
3.3 Preparative experiments
3.3.1 Limit of the detection system
3.3.2 Reflectivity and transmittance of the plate and PBS combination
3.3.3 Autocorrelator
Chapter IV Hybrid Mode-Locked Semiconductor Laser with a SBR: Results and Discussions
4.1 Introduction
4.2 Active mode locking semiconductor laser system
4.2.1 Mode locking with an output coupler cavity
4.2.2 Mode locking with a focusing cavity
4.3 Hybrid mode locking semiconductor laser system
4.3.1 Hybrid mode locking pulse
4.3.2 Hybrid mode locking with a Arsenic-ion-bombarded SBR
Chapter V Conclusions and future works
5.1 Conclusions
5.2 Future works

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