半導體雷射主動鎖模臨界條件之研究

Abstract

本論文以行波速率方程式為基礎，以部分積分法模擬，深入探討主動鎖模 雷射二極體的鎖模行為。本論文改變影響相鎖的四個因素：調變頻率、抗 反射面上的有限反射率、偏壓電流和調變信號振幅並觀察其臨界點變化。 當有限反射率愈小，調移行為愈明顯，較容易得到較短的脈衝，但會有多 重脈衝(multiple pulses)發生。而有限反射率較大者，對於其他三個因 素的改變較不敏感，輸出穩定。此動態調移行為可藉著脈衝峰頂(pulse peak)和增益峰頂(gain peak)之間的相位差加以澄清。 The locking behavior of actively mode-locked laser diode were intensively investigated by partial-integration method, which was derived from traveling-wave rate equations. The dependence of locking threshold on the modulation frequency, finite reflectivity on AR-coated facet, bias current, and modulation amplitude were examined. The lower the finite reflectivity was, the more shorter the pulse was. And the multiple pulses were observed as the driving frequency was close to the external cavity frequency. The pulse width was to some extent insensitive to the controlling factors for high reflectivity case. The behavior of above features were able to be clarfied by the dynamic detuning caused from phase difference between pulse peak and gain peak.