石墨烯对纳米多孔金局域表面等离激元共振的调控

打开文本图片集

中图分类号：TB133文献标志码：A

Graphene modulation of localized surface plasmon resonance in nanoporous gold

LI Zhexiao， JING Zhiyu， ZHANG Ling （School of Optical-Electrical and Computer Engineering， University of Shanghai for Science and Technology， Shanghai 200093， China）

Abstract： In this paper， by characterizing two samples， nanoporous gold （NPG） and graphenecoated nanoporous gold ， using scattering near-field scanning optical microscopy （sSNOM）， it is found that graphene can weaken the localized surface plasmon resonance （LSPR） intensity of NPG. In order to investigate the reason why graphene weakens the hotspot of NPG， this paper analyzes the phenomenon by using finite-difference time-domain simulation， and the simulation results are consistent with the characterization results of s-SNOM. From the absorption spectra of the two samples， we find that graphene can eliminate the phenomenon of multiple LSPR modes caused by the irregular structure of NPG. The simulation results of graphene-coated gold nanoparticles show that the peak position of the LSPR peak of graphene-coated NPs shows an obvious red shift and the peak width increases， indicating that the lifetime of the plasmon isattenuated. This explains why the near-field signal intensity of G@parrowGG is weaker than that of NPG， and why graphene can eliminate the multiple LSPR modes of NPG. In the design of wavelength-selective NPG devices， graphene can be used as an alternative material to modulate the LSPR of nanoporous gold.

Keywords： localized surface plasmon resonance; graphene; nanoporous gold; scattering near-field scanning optical microscopy; finite difference time domain method

引言

近年来，随着纳米技术和光学科技的迅猛发展，局域表面等离激元共振（localizedsurfaceplasmonresonance，LSPR）引起了广泛关注。（剩余9085字）