磁光材料Verdet常数贡献性的讨论

Verdet常数是表征材料磁光性能的重要参数,具有波长和温度依赖性.为了更好地分析入射光波长、温度等对Verdet常数的影响机理,从基础理论切入,分析了现有理论的优缺点.结合光的波粒二象性特性,提出了波动跃迁性贡献理论,即法拉第效应是光的波动性作用以及电偶极跃迁作用带来的贡献之和,波动性对偏转角的贡献为正,跃迁性贡献为负.在抗磁性材料中,波动性贡献大于跃迁性贡献,Verdet常数为正;顺磁性材料中,跃迁性贡献远大于波动性贡献,Verdet常数为负.进而分别以典型抗磁性材料重火石玻璃ZF1和顺磁性材料铽镓石榴石为例,并结合相关数据、参数、模型,对理论进行了验证.试验结果表明,在精确描述材料Verdet常数方面,波动跃迁性贡献理论具有一定的优越性.

Contributions to Verdet constant of magneto-optical materials

Verdet constant is one of the key parameters to characterize the material magneto-optical properties, and dependent on wavelength and temperature. In order to thoroughly analyze the influence mechanisms of the incident wavelength and temperature on the Verdet constant and then uncover its essence, both the advantages and disadvantages of the classical electronic dynamics theory and quantum theory are discussed on account of basic theories and test data. However, neither of the two theories can be separately used to fully explain the Verdet constant and the correlative test data. Therefore, based on the essential property of the magneto-optical effect, the interactions between the incident light and magnetic matter in a magnetic field are studied, and then a hypothesis which suggests that the Faraday effect result from the combination of various factors is proposed. Furthermore, a theory of wave-transition contribution to the Verdet constant is deduced by adopting the theory of wave-particle duality. That is, the Faraday effect is caused by two different contributions simultaneously. One is the wave contribution, which is the interaction between the wave aspect of light and the magneto-optical medium, and the other refers to the transition contribution, which comes from the electronic transition. When the light enters into a deflection angle, the wave contribution is positive while the transition contribution is negative. In a diamagnetic material, since the wave contribution is greater than the transition contribution, the diamagnetic Verdet constant is positive while in a paramagnetic material, on the contrary, the transition contribution is much larger than the wave contribution, so the paramagnetic Verdet constant is negative. According to the above-mentioned theory, the diamagnetic Verdet constant model and the paramagnetic Verdet constant model are proposed by combining the two parts together. Taking the typical diamagnetic material ZF1 and the typical paramagnetic terbium gallium garnet for example, the influences of the incident wavelength and the temperature on the Verdet constant are analyzed, and the deduced theory together with the corresponding models is tested and verified by analyzing the relevant parameters and the test data. Accordingly, the research turns out that the theoretical results correspond to the real values, which proves the rationality of the hypothesis and the authenticity of the deduced theory. Compared with the traditional theories, the wave-transition contribution theory and its model are superior in the sense of precisely describing the material Verdet constant.