Brissinger D, Lereu A L, Salomon L, Charvolin T, Cluzel B, Dumas C, Passian A, de Fornel F
Groupe d'Optique de Champ Proche, LICB, UMR CNRS 5209, Université de Bourgogne, Dijon, France.
Opt Express. 2011 Aug 29;19(18):17750-7. doi: 10.1364/OE.19.017750.
Metal-dielectric transitions are important structures that can display a host of optical characteristics including excitation of plasmons. Metal-dielectric discontinuities can furthermore support plasmon excitation without a severe condition on the incident angle of the exciting photons. Using a semi-infinite thin gold film, we study surface plasmon (SP) excitation and the associated electromagnetic near-field distribution by recording the resulting plasmon interference patterns. In particular, we measure interference periods involving SPs at the scanable metal/air interface and the buried metal/glass one. Supported by optical near-field simulations and experiments, we demonstrate that the metal/glass surface plasmon is observable over a wide range of incident angles encompassing values above and below the critical incident angle. As a result, it is shown that scanning near-field microscopy can provide quantitative evaluation of the real part of the buried surface plasmon wavevector.
金属-电介质转变是重要的结构，可展现出包括等离子体激元激发在内的一系列光学特性。此外，金属-电介质不连续性能够支持等离子体激元激发，而对激发光子的入射角没有严苛要求。我们使用半无限薄金膜，通过记录产生的等离子体干涉图样，研究表面等离子体（SP）激发及相关的电磁近场分布。特别地，我们测量了在可扫描的金属/空气界面和埋入的金属/玻璃界面处涉及表面等离子体的干涉周期。在光学近场模拟和实验的支持下，我们证明在包含高于和低于临界入射角值的宽入射角范围内，金属/玻璃表面等离子体是可观测的。结果表明，扫描近场显微镜能够对埋入表面等离子体波矢的实部进行定量评估。
