Fano resonance boosted cascaded optical field enhancement in a plasmonic nanoparticle-in-cavity nanoantenna array and its SERS application

作     者：Zhendong Zhu Benfeng Bai Oubo You Qunqing Li Shoushan Fan 

作者机构：State Key Laboratory of Precision Measurement Technology and InstrumentsDepartment of Precision InstrumentTsinghua UniversityBeijing 100084China TsinghuaFoxconn Nanotechnology Research CenterDepartment of PhysicsTsinghua UniversityBeijing 100084China 

出 版 物：《Light(Science & Applications)》 (光（科学与应用)（英文版）)

年 卷 期：2015年第4卷第1期

页      面：330-336页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：We acknowledge the support by the National Natural Science Foundation of China(Projects No.11474180,and No.61227014) the Ministry of Science and Technology of China(Project No.2011BAK15B03) 

主　　题：cascaded optical field enhancement Fano resonance localized surface plasmon plasmonic nanoantenna surfaceenhanced Raman spectroscopy 

摘      要：Cascaded optical field enhancement(CFE)can be realized in some specially designed multiscale plasmonic nanostructures,in which the generation of extremely strong fields at nanoscale volume is crucial for many applications,for example,surface-enhanced Raman spectroscopy(SERS).In this paper,we propose a strategy for realizing a high-quality plasmonic nanoparticle-in-cavity(PIC)nanoantenna array,in which strong coupling between a nanoparticle(NP)dark mode with a high-order nanocavity bright mode can produce strong Fano resonance at the target *** Fano resonance can effectively boost the CFE in a PIC.A cost-effective and reliable nanofabrication method is developed using room temperature nanoimprinting lithography to manufacture high-quality PIC *** technique guarantees the generation of only one gold NP at the bottom of each nanocavity,which is crucial for the generation of the expected *** demonstrate the performance and application of the PIC array,the PIC array is employed as an active SERS substrate for detecting 4-aminothiophenol *** experimental SERS enhancement factor of 2×10^(7) is obtained,which verifies the field enhancement and the potential of this device.