TY - JOUR
T1 - Advantage of multi-mode sapphire optical fiber for evanescent-field SERS sensing
AU - Chen, Hui
AU - Tian, Fei
AU - Chi, Jingmao
AU - Kanka, Jiri
AU - Du, Henry
N1 - Publisher Copyright:
© 2014 Optical Society of America
PY - 2014/10/15
Y1 - 2014/10/15
N2 - An unclad, multi-mode single crystal sapphire fiber was used as a platform, and immobilized colloidal Ag nanoparticles (NPs) were used as enabler, for evanescent-field fiber-optic sensing via surface-enhanced Raman scattering (SERS) of Rhodamine 6G (R6G) solution. The dependence of the measured Raman intensity on NP coverage density (to a maximum of 120 particles/μm2) as well as the coverage length (to a maximum of 6 cm) was investigated. We demonstrate the utility of SERS-active sapphire fibers for sensitive measurements (10-8 M R6G). We further reveal, with the aid of theoretical analysis, that multi-mode fiber offers a significant advantage compared to its single-mode counterpart because the former allows two orders of magnitude higher particle coverage density than the latter to maximize SERS benefit, while maintaining the dominance of Raman gain despite the competitive interplay of NP-induced absorption and scattering loss along the interaction path length.
AB - An unclad, multi-mode single crystal sapphire fiber was used as a platform, and immobilized colloidal Ag nanoparticles (NPs) were used as enabler, for evanescent-field fiber-optic sensing via surface-enhanced Raman scattering (SERS) of Rhodamine 6G (R6G) solution. The dependence of the measured Raman intensity on NP coverage density (to a maximum of 120 particles/μm2) as well as the coverage length (to a maximum of 6 cm) was investigated. We demonstrate the utility of SERS-active sapphire fibers for sensitive measurements (10-8 M R6G). We further reveal, with the aid of theoretical analysis, that multi-mode fiber offers a significant advantage compared to its single-mode counterpart because the former allows two orders of magnitude higher particle coverage density than the latter to maximize SERS benefit, while maintaining the dominance of Raman gain despite the competitive interplay of NP-induced absorption and scattering loss along the interaction path length.
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U2 - 10.1364/OL.39.005822
DO - 10.1364/OL.39.005822
M3 - Article
C2 - 25361094
AN - SCOPUS:84908102161
SN - 0146-9592
VL - 39
SP - 5822
EP - 5825
JO - Optics Letters
JF - Optics Letters
IS - 20
ER -