A one-dimensional multilayer structure consisting of two symmetric parts with defect layers is designed, and properties of the multiple nonreciprocal transmission are investigated due to symmetrically distributed magneto-optic layers with opposite magnetic fields in composite structures. The transmission coefficient and energy band diagram of the system are obtained based on transfer matrix method. The numerical results show that there are three pairs of nonreciprocal dispersive curves with different modes in a certain bandgap. The influence of the thickness of defect layer and incident angle on nonreciprocal frequencies is also discussed. The multiple nonreciprocal transmission could in turn be potentially useful in optical isolators and optical resonators.

中文翻译：

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基于光子晶体缺陷模式的多重不可逆传输

设计了由两个带有缺陷层的对称部分组成的一维多层结构，并研究了复合结构中对称分布的具有相反磁场的磁光层的多重不可逆传输特性。基于传递矩阵法得到系统的传输系数和能带图。数值结果表明，在一定带隙内存在三对不同模式的非互易色散曲线。还讨论了缺陷层厚度和入射角对不可逆频率的影响。多重不可逆传输又可能在光学隔离器和光学谐振器中发挥潜在作用。