Effects of thickness & shape on localized surface plasmon resonance of sexfoil nanoparticles  

作　　者：Yan Chen Xianchao Liu Weidong Chen Zhengwei Xie Yuerong Huang Ling Li 陈艳;刘贤超;陈卫东;谢征微;黄跃容;李玲(College of Physics and Electronic Engineering,Sichuan Normal University;State Key Laboratory of Electronic Thin Films and Integrated Devices,School of Optoelectronic Information,University of Electronic Science and Technology)

机构地区：[1]College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu 610101, China [2]State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology, Chengdu 610054, China

出　　处：《Chinese Physics B》2017年第1期508-513,共6页中国物理B（英文版）

基　　金：supported by the Sichuan Provincial Department of Education,China(Grant No.16ZA0047);the State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,China(Grant No.201509);the Large Precision Instruments Open Project Foundation of Sichuan Normal University,China(Grant Nos.DJ201557,DJ201558 and DJ201560);the State Key Laboratory of Optical Technologies on Nano Fabrication and Micro Engineering,Institute of Optics and Electronics,Chinese Academy of Sciences

摘　　要：Localized surface plasmon （LSPR） resonance and sensing properties of a novel nanostructure （sexfoil nanoparticle） are studied using the finite-difference time-domain method. For the sandwich sexfoil nanoparticle, the calculated extinction spectrum shows that with the thickness of the dielectric layer increasing, long-wavelength peaks blueshift, while short- wavelength peaks redshift. Strong near-field coupling of the upper and lower metal layers leads to electric and magnetic field resonances; as the thickness increases, the electric field resonance gradually increases, while the magnetic field resonance decreases. The obtained refractive index sensitivity and figure of merit are 332 nm/RIU and 3.91 RIU^-1, respectively. In order to obtain better sensing ability, we further research the LSPR character of monolayer Ag sexfoil nanoparticle. After a series of trials to optimize the thickness and shape, the refractive index sensitivity approximates 668 nm/RIU, and the greatest figure of merit value comes to 14.8 RIU^-1.Localized surface plasmon （LSPR） resonance and sensing properties of a novel nanostructure （sexfoil nanoparticle） are studied using the finite-difference time-domain method. For the sandwich sexfoil nanoparticle, the calculated extinction spectrum shows that with the thickness of the dielectric layer increasing, long-wavelength peaks blueshift, while short- wavelength peaks redshift. Strong near-field coupling of the upper and lower metal layers leads to electric and magnetic field resonances; as the thickness increases, the electric field resonance gradually increases, while the magnetic field resonance decreases. The obtained refractive index sensitivity and figure of merit are 332 nm/RIU and 3.91 RIU^-1, respectively. In order to obtain better sensing ability, we further research the LSPR character of monolayer Ag sexfoil nanoparticle. After a series of trials to optimize the thickness and shape, the refractive index sensitivity approximates 668 nm/RIU, and the greatest figure of merit value comes to 14.8 RIU^-1.

关 键 词：sexfoil nanoparticle localized surface plasmon resonance extinction properties LSPR sensors 

分 类 号：TB383.1[一般工业技术—材料科学与工程] O53[理学—等离子体物理]