论文部分内容阅读
光子晶体中引入缺陷后将形成缺陷模,这些缺陷模在增益介质中将被放大形成激光。基于麦克斯韦方程和速率方程相结合的模型,用时域有限差分法(FDTD)计算和分析了一维单缺陷光子晶体激光器中缺陷模的空间分布和频谱特性,以及这些缺陷模的放大特性,主要研究了缺陷层的厚度、晶体层数对缺陷模放大特性的影响。模拟结果显示,类似于传统激光腔的腔模,这些缺陷模能够被放大,形成激光。调整缺陷层的厚度、晶体层数等结构参量,将改变缺陷模的谐振,激射频率以及空间分布,这将直接影响激射阈值和饱和特性。增加晶体的层数,激光器的阈值将降低,饱和值将增加,但晶体层数增加到一定限度时,这种增减趋势变弱。模拟结果证明了有效层数的存在。
The introduction of defects into the photonic crystal will form defect modes that will be amplified in the gain medium to form a laser. Based on Maxwell’s equations and rate equations, the spatial distribution and spectral characteristics of defect modes in one-dimensional single-defect photonic crystal lasers and the amplification characteristics of these defect modes are calculated and analyzed by FDTD. The influence of the thickness of the defect layer and the number of crystal layers on the amplification characteristics of the defect mode was investigated. Simulation results show that, similar to the cavity mode of a conventional laser cavity, these defect modes can be magnified to form a laser. Adjusting the thickness of the defect layer, the crystal layer number and other structural parameters will change the resonance mode, the lasing frequency and the spatial distribution of the defect mode, which will directly affect the lasing threshold and saturation characteristics. Increase the number of crystals, the laser threshold will be reduced, the saturation value will increase, but the crystal layer increases to a certain limit, the trend of such increase and decrease. The simulation results prove the existence of effective layers.