Waveguide excitation and collection of surface-enhanced Raman scattering from a single plasmonic antenna

Nanophotonics

article

Frédéric Peyskens¹  Pieter Wuytens¹  Ali Raza¹  Pol Van Dorpe¹  Roel Baets¹ 

[1] Photonics Research Group, INTEC Department, Ghent University-IMEC;Center for Nano- and BioPhotonics;Quantum Photonics Group, Massachusetts Institute of Technology;Department of Physics

关键词: integrated photonics;    plasmonics;    surface-enhanced Raman spectroscopy;   

DOI  :  10.1515/nanoph-2018-0003

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

The integration of plasmonic antennas on single-mode silicon nitride waveguides offers great perspective for integrated surface-enhanced Raman spectroscopy (SERS). However, the few reported experimental demonstrations still require multiple plasmonic antennas to obtain a detectable SERS spectrum. Here, we show, for the first time, SERS signal detection by a single nanoplasmonic antenna integrated on a single-mode SiN waveguide. For this purpose, we investigated a backscattering detection scheme in combination with background noise reduction, which allowed an optimization of the signal-to-noise ratio (SNR) of this platform. Furthermore, a comparison with the free-space SERS spectrum of the same antenna shows that the conversion efficiency from pump power to total radiated Stokes power is twice as efficient in the case of waveguide excitation. As such, we explored several important aspects in the optimization of on-chip SERS sensors and experimentally demonstrated the power of exciting nanoplasmonic antennas using the evanescent field of a waveguide. This observation not only is useful for Raman sensing but also could be beneficial for any process involving plasmonic enhancement.

【 授权许可】

CC BY