Grating-assisted coupling enhancing plasmonic tip nanofocusing illuminated via radial vector beam
Autor: | Lu Fanfan, Zhang Wending, Zhang Jiachen, Liu Min, Zhang Lu, Xue Tianyang, Meng Chao, Gao Feng, Mei Ting, Zhao Jianlin |
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Jazyk: | angličtina |
Rok vydání: | 2019 |
Předmět: | |
Zdroj: | Nanophotonics, Vol 8, Iss 12, Pp 2303-2311 (2019) |
Druh dokumentu: | article |
ISSN: | 2192-8606 2192-8614 |
DOI: | 10.1515/nanoph-2019-0329 |
Popis: | Tip-enhanced Raman spectroscopy (TERS) is a very useful method to achieve label-free and super-resolution imaging, and the plasmonic tip nanofocusing plays a decisive role for TERS performance. Here, we present a method to enhance the nanofocusing characteristic of a plasmonic tip integrated in a grating near the tip apex. Simulation results show that the grating near the tip apex can significantly improve the electric field intensity of the nanofocusing field compared with a conventional bare tip, under axial excitation of a tightly focused radial vector beam. The electric field enhancement characteristic is quantified in relation with the groove number of grating, excitation wavelength, period of grating, and numerical aperture of the micro-objective (MO). These simulation results could be a good reference to fabricate a plasmonic tip for TERS applications, which is an effective way to promote the development of tip-enhanced near-field optical microscopy. |
Databáze: | Directory of Open Access Journals |
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