Setälä Tero, Kaivola Matti, Friberg Ari T
Department of Engineering Physics and Mathematics, Helsinki University of Technology, P.O. Box 2200, FIN-02015 HUT, Finland.
Phys Rev Lett. 2002 Mar 25;88(12):123902. doi: 10.1103/PhysRevLett.88.123902. Epub 2002 Mar 7.
We introduce the concept of degree of polarization for electromagnetic near fields. The approach is based on the generalized Stokes parameters that appear as expansion coefficients of the 3 x 3 coherence matrix in terms of the Gell-Mann matrices. The formalism is applied to optical near fields of thermally fluctuating half-space sources with particular interest in fields that are strongly polarized owing to resonant surface plasmons or phonons. This novel method is particularly useful when assessing the full vectorial characteristics of random evanescent fields, e.g., for near-field spectroscopy and polarization microscopy.
我们引入了电磁近场极化度的概念。该方法基于广义斯托克斯参数，这些参数表现为3×3相干矩阵在盖尔曼矩阵方面的展开系数。该形式体系应用于热涨落半空间源的光学近场，特别关注由于共振表面等离子体激元或声子而强烈极化的场。当评估随机倏逝场的全矢量特性时，例如对于近场光谱学和偏振显微镜，这种新方法特别有用。
