Open AccessUltrahigh Enhancement Factor by Using a Silver Nanoshell With a Gain Core Above a Silver Substrate for Surface-Enhanced Raman Scattering at the Single-Molecule Level
Author(s) -
Jun Song,
Jinhong Xian,
Minghuai Yu,
Dong Wang,
Shuai Ye,
Hanben Niu,
Xiao Peng,
Junle Qu
Publication year - 2015
Publication title -
ieee photonics journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.725
H-Index - 73
eISSN - 1943-0655
pISSN - 1943-0647
DOI - 10.1109/jphot.2015.2481599
Subject(s) - engineered materials, dielectrics and plasmas , photonics and electrooptics
Single-molecule surface-enhanced Raman scattering (SERS) has been extensively studied over the past decade. In this paper, we propose a novel method to obtain ultrahigh enhancement of local electric fields by using a silver nanoshell with a gain core above a silver substrate. Numerical results show that an ultrahigh enhancement factor of the local electric field on the order of 105-106 and a SERS enhancement factor on the order of 1020-1025 can be obtained with the present system. The SERS enhancement factor is five orders of magnitude greater than the highest theoretical value reported for SERS applications at the single-molecule level. In addition, we use the finite-element method to analyze in detail the influences of the gain coefficient of the gain core and the other structure parameters on the enhancement factor.