Multipole plasmon resonances in self-assembled metal hollow-nanospheres
Multipole plasmon resonances in self-assembled metal hollow-nanospheres
复制标题
自组装金属空心纳米球中的多极等离子体共振
DOI：
10.1039/c3nr04106a
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发表时间：
2014-01-01
期刊：
影响因子：
6.7
通讯作者：
Li, Jing
中科院分区：
文献类型：
--
作者：
Yin, Jun;Zang, Yashu;Li, Jing
近年来，金属空心结构中的多极等离子体激元模式共振，如偶极、四极和八极等离子体激元模式，在生物传感、荧光、纳米激光或非线性纳米光子学等领域有着广泛的应用前景。本文从理论和实验两方面研究了自组装金属空心纳米球（HNS）中的多极等离子体共振，并提出了利用高阶模等离子体共振和粒子间耦合效应产生的热点来增强拉曼散射。偶极、四极、八极和十六极模式等离子体共振在这些Ag HNS阵列的消光光谱中被清楚地分辨出来，与理论模拟结果吻合得很好。通过高阶模等离子体激元共振和相应的粒子间耦合效应，在Ag HNS的表面周围和间隙中获得了较强的规则热点。通过优化HNS的尺寸以及HNS之间的耦合距离，实现了最大的局域场强，并将其应用于Sers传感。拉曼映射也证明了这些自组装的等离子体腔阵列是稳定和均匀的SERS活性基底。
Recently, multipole plasmonic mode resonances in metal hollow structures, such as dipole, quadrupole, and octupole modes, have been widely investigated by researchers with the aim for potential applications in bio-sensing, fluorescence, nanolasers or nonlinear nano-photonics. Here, in this work, the multipole plasmon resonances in self-assembled metal hollow-nanospheres (HNSs) are theoretically and experimentally demonstrated and the hot spots originating from the higher order mode plasmonic resonance and interparticle coupling effect are proposed to be used for Raman scattering enhancements. Dipole, quadrupole, octupole and hexadecapole mode plasmonic resonances were clearly resolved in the extinction spectra of these Ag HNS arrays showing good agreement with the theoretical simulation results. Strong regular hot spots were obtained around the surface and in the gaps of the Ag HNSs through the higher order mode plasmonic resonances and corresponding interparticle coupling effect between the HNSs. Maximum local field intensity was accomplished by optimizing the size of as well as the coupling distance between the HNSs and then it was applied to SERS sensing. Raman mapping also demonstrated these self-assembled plasmonic cavity arrays to be a stable and uniform SERS-active substrate.