The loss is greater when the imaginary part of the complex dielectric constant is bigger and the mode order is higher.

介电常数虚部大（绝对值），而且包层模序也大时，损耗较大。

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The transfer matrix method is used to calculate the band structures of 1D crystals with complex dielectric constant, in this paper, The authors put emphasis on the case of negative imaginary part.

利用传输矩阵法计算了一维光子晶体的能带结构和光传输特性，重点讨论了介电常量的虚部为负值时对传输特性的影响。

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