Electro-Optics Program, University of Dayton, Dayton, Ohio 45469, USA.
Opt Lett. 2012 May 1;37(9):1442-4. doi: 10.1364/OL.37.001442.
The spin dependence of the focusing behavior of a spiral slot plasmonic lens can be utilized for a miniature circular polarization analyzer. However, the azimuthal polarization component of the incident circular polarization does not contribute to surface plasmon excitation and focusing because it is TE polarized with respect to the spiral slot. In this Letter, a hybrid metallic lens that consists of alternating spiral triangle array and spiral slot is designed to improve the plasmonic coupling efficiency. The spiral triangle array is responsible for coupling the azimuthal polarization component into surface plasmon. Numerical studies show that the field enhancement at the focus and power conversion efficiency can be increased by 39.53% and 94.69% compared to that of pure spiral slot plasmonic lens.
螺旋槽等离子体透镜的聚焦行为的自旋依赖性可用于微型圆偏振分析仪。然而，由于相对于螺旋槽而言，入射圆偏振的角向偏振分量为 TE 偏振，因此它不会有助于表面等离激元的激发和聚焦。在本信中，设计了一种由交替的螺旋三角形阵列和螺旋槽组成的混合金属透镜，以提高等离子体耦合效率。螺旋三角形阵列负责将角向偏振分量耦合到表面等离激元中。数值研究表明，与纯螺旋槽等离子体透镜相比，焦点处的场增强和功率转换效率可以分别提高 39.53%和 94.69%。
