比較π/2相位移分佈回授半導體雷射與線性漸變式光柵的π/2相位移分佈回授半導體雷射之間的優劣

Abstract

在傳統的半導體雷射中,π/2相位移分佈回授半導體雷射在高於起始電流 以上的電流操作下,因為光強度在雷射共振腔內的不均勻分布,造成載子分 布不均,影響其單模光的穩定性.我們提出了三種線性漸變式光柵結構的 π/2相位移分佈回授半導體雷射,與傳統的π/2相位移分佈回授半導體雷 射比較,希望在高的電流操作下仍保持其單模特性與高速調變下的窄頻特 性,在結論中可知線性漸變式光柵結構的π/2相位移分佈回授半導體雷射 確實能達到抑制載子分布不均造成改變單模光特性的現象. Conventional quarter wave phase shift DFB laser has very serious spatial hole buring effect at the above threshold condition which results in lasing mode unstable at high current level.But chirped grating structure DFB laser may reduce the effect of spatial hole buring or increasing the threshold gain difference to keep the single mode lasing property and narrow linewidth under high speed modulation.We analized and simulated three different chirped grating DFB lasers in this report.Our results show great promising for these chirped grating DFB lasers in suppressing spatial hole burning effect for high single mode yield at the above threshold condition.