使用金属包覆磁性波导中的磁光耦合理论分析了静磁表面波与导波光在金属／电介质／钇铁石榴石／钆镓石榴石结构中的磁光共线作用，讨论了金属覆层和斜向场对磁光模式转换效率的影响。计算表明，金属包覆波导可以提高磁光作用，通过调节金属覆层与磁性薄膜间距得到了比空气／钇铁石榴石／钆镓石榴石的传统三明治波导情形高8．7dB的模式转换效率；而同时优化偏置磁场方向和金属包覆波导参数，模式转换效率可以进一步提高5．25dB。因此，金属包覆波导可以用于提高磁光Bragg器件性能，在微波和光信息处理等方面具有广阔的应用前景。

The magnetic-optic(MO)collinear interaction between the magnetostatic surface waves(MSSWs)and the guided optical waves(GOWs)was analyzed by the MO coupled-mode theory of the metal clad magnetized waveguide in the metal/dielectric/yttrium-iron-garnet(YIG)/yadolinium-gallium-garnet(GGC)structure. The enhancement of the mode conversion efficiency(MCE)by the metal layer and the bias magnetic field was discussed. The results show that the MCE can be improved by the metal clad waveguide. The MCE enhancement of 8.7 dB is obtained comparing with the case of the air/YIG/GGG conventional sandwich waveguide. The NCE can be further improved by simultaneously adjusting the spacing of the metal layer from the YIG film and the magnetized direction. Therefore, the metal clad waveguide can be used to enchance the performance of the MO Bragg cell, which will be widely used in the microwave and optical signal processing.