Excitation and propagation of surface plasmon polaritons on a non-structured surface with a permittivity gradient  

作　　者：Xi Wang Yang Deng Qitong Li Yijing Huang Zilun Gong Kyle B Tom Jie Yao 

机构地区：[1]Department of Materials Science and Engineering,University of California,Berkeley,CA 94720,USA [2]Environmental Energy Technologies Division,Lawrence Berkeley National Laboratory,Berkeley,CA 94720,USA [3]Materials Sciences Division,Lawrence Berkeley National Laboratory,Berkeley,CA 94720,USA

出　　处：《Light(Science & Applications)》2016年第1期365-370,共6页光（科学与应用)（英文版）

基　　金：supported by the Samsung Advanced Institute of Technology under the Grant 037361-003;the Hellman Family Foundation.

摘　　要：Accompanied by the rise of plasmonic materials beyond those based on noble metals and the development of advanced materials processing techniques,it is important to understand the plasmonic behavior of materials with large-scale inhomogeneity(such as gradient permittivity materials)because they cannot be modeled simply as scatterers.In this paper,we theoretically analyze the excitation and propagation of surface plasmon polaritons(SPPs)on a planar interface between a homogeneous dielectric and a material with a gradient of negative permittivity.We demonstrate the following:(i)free-space propagating waves and surface waves can be coupled by a gradient negative-permittivity material and(ii)the coupling can be enhanced if the material permittivity variation is suitably designed.This theory is then verified by numerical simulations.A direct application of this theory,‘rainbow trapping’,is also proposed,considering a realistic design based on doped indium antimonide.This theory may lead to various applications,such as ultracompact spectroscopy and dynamically controllable generation of SPPs.

关 键 词：gradient negative permittivity non-structured surface rainbow trapping surface plasmonics 

分 类 号：TB3[一般工业技术—材料科学与工程]