标题： 关于线性磁电材料中光传播的备注 显示英文标题

标题： Remarks on light propagation in linear magnetoelectric materials

摘要： 光在一种线性磁电晶体介质中的传播研究通常假设电场$\boldsymbol{E}$和辅助场$\boldsymbol{H}$是决定材料的极化$\boldsymbol{P}$和磁化$\boldsymbol{M}$的变量。 这种选择导致了电、磁和磁电极化率的标准定义。 这里建议将法拉第电磁感应定律中出现的电磁场$\boldsymbol{E}$和$\boldsymbol{B}$作为$\boldsymbol{P}$和$\boldsymbol{M}$的变量，这可以简化某些线性光学效应的数学描述。 光学系数与介质折射率之间的关系变得更加直接。 特别是，磁电系数可以巧妙地用折射率来表示，而无需对其大小与其他线性系数进行任何近似。 这种形式化方法对于连接与磁电效应及其应用相关的理论和实验可能有帮助。 还对磁化率的定义及其在电磁学一些著名公式中的使用进行了简要讨论。 显示英文摘要

摘要： The study of light propagation in a linear magnetoelectric crystalline medium typically assumes that the electric field $\boldsymbol{E}$ and the auxiliary field $\boldsymbol{H}$ are the variables that determine the polarization $\boldsymbol{P}$ and magnetization $\boldsymbol{M}$ of the material. This choice leads to the standard definitions of the electric, magnetic and magnetoelectric susceptibilities. It is here suggested that the use of the electromagnetic fields $\boldsymbol{E}$ and $\boldsymbol{B}$, which appear in the Faraday induction law, as variables for $\boldsymbol{P}$ and $\boldsymbol{M}$, simplifies the mathematical description of some linear optical effects. The relationship between the optical coefficients and the refractive index of the medium becomes more straightforward. Particularly, the magnetoelectric coefficient can be deftly expressed in terms of the refractive index without the need for any approximation regarding its magnitude compared to the other linear coefficients. This formalism can be useful for connecting theory and experiments related to the magnetoelectric effect and its applications. A short discussion on the definition of the magnetic susceptibility and its use in some well known formula of the electromagnetism is also provided.