回音壁微腔激光器噪声特性数值模拟研究(特邀)  

Numerical Simulation of Noise Characteristics for WGM Microcavity Lasers(Invited)

作　　者：刘家辰 黄永箴[1,2] 郝友增 杨珂 杨跃德 肖金龙[1,2] LIU Jiachen;HUANG Yongzhen;HAO Youzeng;YANG Ke;YANG Yuede;XIAO Jinlong(State Key Laboratory of Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院半导体研究所集成光电子学国家重点实验室,北京100083 [2]中国科学院大学材料科学与光电工程中心,北京100049

出　　处：《光子学报》2022年第2期62-71,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(No.61935018);北京市科学技术委员会(No.Z201100004020007)。

摘　　要：通过建立包含朗之万噪声源的三模速率方程模型,模拟研究了回音壁模式微腔激光器的噪声特性和线宽特性,特别是注入电流热效应引起的跳模及其对光功率和实现窄线宽的影响。回音壁微腔激光器单模工作时,在大偏置电流下可由低频处的频率噪声得到百kHz以下的激光器线宽;在微腔双模激射状态下,由于模式竞争作用,微腔激光器的相对强度噪声和频率噪声在低频处都有明显的升高,使得激光器的线宽展宽。此外,还采用快速傅里叶变换的方法由时域信号计算获得激光模式光谱线型,由此得到的激光模式线宽与通过频率噪声谱获得的线宽基本一致。In this paper,by establishing a tri-mode rate equation model with a gain spectrum model and Langevin noise sources,the relative intensity noise,frequency noise and linewidths of a WGM microcavity laser are investigated numerically,and the influence of the mode competition on noise characteristics of the microcavity lasers is mainly studied.The steady-state characteristics of the microcavity laser are simulated by the tri-mode rate equation model including carrier densities,photon densities and mode phases.The mode skipping due to the thermal effect caused by the injection current is simulated.As the temperature increases due to the current injection,the lasing wavelength of the microcavity laser redshifts and the mode skips with the increase of the injection current.The effect on the optical power,relative intensity noise,frequency noise and linewidths are studied by inducing Langevin noise sources to the rate equations.When the microcavity laser is at a single-mode lasing state,the relaxation oscillation peaks of the relative intensity noise and frequency noise spectra both move to the high frequency with the increase of the injection current,and the whole relative intensity noise and frequency noise decrease.Relative intensity noise refers to the ensemble average of the fluctuations of the laser power relative to the average power squared.The relative intensity noise approaches the standard quantum limit of-165.5 dB/Hz at a high bias current of 115 mA,a long integral time of 50μs and a short time step of 1 ps.The frequency noise of the laser refers to the random fluctuation of instantaneous mode frequency,which comes from the natural phase noise of the laser caused by the spontaneous emission,and phase noise caused by carrier fluctuation.And the linewidth of the microcavity laser,which is the full-width at half-maximum of the single-mode spectrum,is determined from the low-frequency of the frequency noise spectrum.By averaging the frequency noise at the low-frequency of the frequency noise spectrum,a low linew

关 键 词：半导体微腔激光器 相对强度噪声 相位噪声 频率噪声 线宽 

分 类 号：TN365[电子电信—物理电子学]