Maier Stefan A
Opt Express. 2006 Mar 6;14(5):1957-64. doi: 10.1364/oe.14.001957.
The controlled creation of nanometric electromagnetic field confinement via surface plasmon polariton excitations in metal/insulator/metal heterostructures is described via the concept of an effective electromagnetic mode volume Veff. Extensively used for the description of dielectric microcavities, its extension to plasmonics provides a convenient figure of merit and allows comparisons with dielectric counterparts. Using a one-dimensional analytical model and three-dimensional finite-difference time-domain simulations, it is shown that plasmonic cavities with nanometric dielectric gaps indeed allow for physical as well as effective mode volumes well below the diffraction limit in the gap material, despite significant energy penetration into the metal. In this picture, matter-plasmon interactions can be quantified in terms of quality factor Q and Veff, enabling a resonant cavity description of surface enhanced Raman scattering.
通过有效电磁模式体积(V_{eff})的概念，描述了在金属/绝缘体/金属异质结构中通过表面等离激元极化激元激发来控制纳米级电磁场限制的方法。(V_{eff})广泛用于描述介电微腔，将其扩展到等离子体学提供了一个方便的品质因数，并允许与介电对应物进行比较。使用一维分析模型和三维时域有限差分模拟表明，尽管有大量能量渗透到金属中，但具有纳米级介电间隙的等离子体腔确实允许在间隙材料中实现远低于衍射极限的物理模式体积和有效模式体积。在此框架下，物质-等离子体相互作用可以根据品质因数(Q)和(V_{eff})进行量化，从而实现对表面增强拉曼散射的共振腔描述。
