磁光隔离器插入损耗与隔离度关键影响因素数学分析

Mathematical analysis of key factors affecting insertion loss and isolation degree of magneto-optical isolator

从定量角度出发,详细分析了磁光隔离器的插入损耗与隔离度的关键影响因素,并给出了具体的数学表达式。从数学原理证明隔离器的插入损耗主要由材料吸收和端面反射率决定,而隔离度主要取决于法拉第旋光微扰角度。法拉第旋光角微扰度与通光波长、环境温度、磁光材料的费尔德常数及厚度、以及偏置磁场强度等因素有关,给出了相关数学表达式,并证明通光波长的变化、温度波动等因素是影响器件隔离度的关键因素。

The key factors affecting insertion loss(IL) and isolation(ISO) of magneto-optic isolator are analyzed quantitatively,and the mathematical expressions of IL and ISO are given in this paper.It is proved from mathematically that the insertion loss is mainly determined by the material absorption and the interface reflectance,and the isolation degree is mainly determined by the perturbation of the Faraday rotation angle.The perturbation of the Faraday rotation angle is related to the wavelength of the light,the ambient temperature,the Verdet constant and thickness of the magneto-optic material,and the bias magnetic field.Related mathematical expressions are also given in this work,and it is further proved that the key factors affecting the isolation degree are the variation of wavelength,temperature fluctuation and magnetic field uniformity.