Influence of tip geometry on the spatial resolution of tip enhanced Raman mapping  

作　　者：张超 陈宝琴 李志远 

机构地区：[1]Laboratory of Optical Physics,Institute of Physics,Chinese Academy of Sciences [2]College of Physics and Optoelectronics,South China University of Technology

出　　处：《Chinese Physics B》2016年第9期415-422,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.11434017);the National Basic Research Program of China(Grant No.2013CB632704)

摘　　要：In 2013,a breakthrough experiment pushed the Raman mapping of molecules via the tip-enhanced Raman scattering（TERS） technique to a sub-nanometer spatial resolution,going into the single-molecule level.This surprising result was well explained by accounting for the critical role of elastic molecule Rayleigh scattering within a plasmonic nanogap in enhancing both the localization and the intensity level of the Raman scattering signal.In this paper,we theoretically explore the influence of various geometric factors of the TERS system on the spatial resolution of Raman mapping,such as the tip curvature radius,tip conical angle,tip–substrate distance,and tip–molecule vertical distance.This investigation can help to find out the most critical geometric factor influencing the spatial resolution of TERS and march along in the right direction for further improving the performance of the TERS system.In 2013,a breakthrough experiment pushed the Raman mapping of molecules via the tip-enhanced Raman scattering（TERS） technique to a sub-nanometer spatial resolution,going into the single-molecule level.This surprising result was well explained by accounting for the critical role of elastic molecule Rayleigh scattering within a plasmonic nanogap in enhancing both the localization and the intensity level of the Raman scattering signal.In this paper,we theoretically explore the influence of various geometric factors of the TERS system on the spatial resolution of Raman mapping,such as the tip curvature radius,tip conical angle,tip–substrate distance,and tip–molecule vertical distance.This investigation can help to find out the most critical geometric factor influencing the spatial resolution of TERS and march along in the right direction for further improving the performance of the TERS system.

关 键 词：tip-enhanced Raman scattering Rayleigh scattering surface plasmon resonance 

分 类 号：O433[机械工程—光学工程]