chapter  9
30 Pages

Multilayer Coupled Nanoplasmonic Structures and Related Computational Techniques

WithMina Ray, Mahua Bera

Surface plasmons (SPs) are collective oscillations of conduction electrons at the surface of a thin metallic lm adjacent to a dielectric layer, resulting in an SP wave (SPW) that propagates along the interface of two materials with their real part of permittivity having opposite signs. SPs are generally excited through a coupling of an evanescent eld generated by incident p-polarized light in the attenuated total reection (ATR) coupler mode. At a certain incident angle greater than the critical angle, if the phase-matching condition is satised, that is, if the wave vector of the SP matches with that of the incident

CONTENTS

9.1 Introduction ........................................................................................................................ 315 9.2 Mathematical Formulations ............................................................................................. 317

9.2.1 Physics of SPR ......................................................................................................... 317 9.2.2 Generalized Mathematical Formulation (N-Layer Model) Based on

Characteristic Transfer Matrix Method .............................................................. 320 9.3 Computational Procedure for Reectivity Calculation ................................................ 322 9.4 Classication of Different Nanoplasmonic Structures ................................................. 322 9.5 Simulation of Resonance Curves for Different Nanoplasmonic Structures ............. 323

9.5.1 2D Resonance Curves ............................................................................................ 323 9.5.2 3D Resonance Curves ............................................................................................ 325

9.5.2.1 Analysis for Conventional SPR Structure ........................................... 325 9.5.2.2 Analysis for Modied Coupled Nanoplasmonic

Resonant Structure ................................................................................. 325 9.6 Metal Thickness Optimization ........................................................................................ 327 9.7 Applications in Nanophotonics .......................................................................................333