Milla M J, Barho F, González-Posada F, Cerutti L, Charlot B, Bomers M, Neubrech F, Tournie E, Taliercio T
Opt Express. 2017 Oct 30;25(22):26651-26661. doi: 10.1364/OE.25.026651.
We demonstrate surface enhanced infrared absorption spectroscopy using 1-dimensional highly doped semiconductors based on Si-doped InAsSb plasmonic nano-antennas. Engineering the plasmonic array to support the localized surface plasmon resonance aligned with the molecular vibrational absorption mode of interest involves finely setting the doping level and nano-antenna width. Heavily doped nano-antennas require a wider size compared to lightly doped resonators. Increasing the doping level, and consequently the width of the nano-antenna, enhances the vibrational absorption of a ~15 nm thick organic layer up to 2 orders of magnitude compared to the unstructured sample and therefore improves sensing. These results pave the way towards molecule fingerprint sensor manufacturing by tailoring the plasmonic resonators to get a maximum surface enhanced infrared absorption at the target vibrational mode.
我们展示了基于硅掺杂砷化铟锑等离子体纳米天线的一维高掺杂半导体的表面增强红外吸收光谱。设计等离子体阵列以支持与感兴趣的分子振动吸收模式对齐的局域表面等离子体共振，需要精确设置掺杂水平和纳米天线宽度。与轻掺杂谐振器相比，重掺杂纳米天线需要更宽的尺寸。增加掺杂水平，进而增加纳米天线的宽度，与非结构化样品相比，可将约15纳米厚的有机层的振动吸收提高多达2个数量级，从而改善传感性能。这些结果为通过定制等离子体谐振器以在目标振动模式下获得最大表面增强红外吸收来制造分子指纹传感器铺平了道路。
