We investigate the two-point polarization correlation properties of random, statistically stationary, two-dimensional (2D) and three-dimensional (3D) electromagnetic fields. To this end two specific mutual polarization correlation functions are introduced, one based on a geometric approach using the Poincaré vectors and the other on the energy distribution employing the Jones vectors. Both approaches provide equivalent information about the space-time polarization correlations and enable one to associate with the field a polarization length over which the equal-time polarization states remain essentially unchanged. For fields obeying Gaussian statistics, the polarization correlation functions take on simple forms in terms of measurable quantities representing electromagnetic coherence. The formalism is demonstrated with two examples: blackbody radiation inside a cavity and in the far zone of a cavity wall aperture.

中文翻译：

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随机近轴和非近轴电磁场的两点极化相关

我们研究了随机、统计平稳、二维 (2D) 和三维 (3D) 电磁场的两点极化相关特性。为此，引入了两个特定的相互极化相关函数，一个基于使用庞加莱矢量的几何方法，另一个基于使用琼斯矢量的能量分布。这两种方法都提供了关于时空极化相关性的等效信息，并使人们能够将一个极化长度与场相关联，在该极化长度上等时极化状态基本保持不变。对于服从高斯统计的场，极化相关函数采用表示电磁相干性的可测量量的简单形式。形式主义用两个例子来证明：