Cavity-enhanced surface-plasmon resonance sensing: modeling and performance

Authors :: Saverio Avino
Gianluca Gagliardi
Jiří Homola
R. Zullo
P. De Natale
Pietro Malara
Antonio Giorgini
Source :: Measurement science & technology, 25 (2014): 015205–015205. doi:10.1088/0957-0233/25/1/015205, info:cnr-pdr/source/autori:Giorgini, A.; Avino, S.; Malara, P.; Zullo, R.; Gagliardi, G.; Homola, J.; De Natale, P./titolo:Cavity-enhanced surface-plasmon resonance sensing: modeling and performance/doi:10.1088%2F0957-0233%2F25%2F1%2F015205/rivista:Measurement science & technology (Print)/anno:2014/pagina_da:015205/pagina_a:015205/intervallo_pagine:015205–015205/volume:25
Publication Year :: 2013
Publisher :: IOP Publishing, 2013.
Abstract: We investigate the performance of a surface-plasmon-resonance refractive-index (RI) sensor based on an optical resonator. The resonator transforms RI changes of liquid samples, interacting with the surface plasmon excited by near-infrared light, into a variation of the intra-cavity optical loss. Cavity ring-down measurements are provided as a proof of concept of RI sensing on calibrated mixtures. A characterization of the overall sensor response and noise features as well as a discussion on possible improvements is carried out. A reproducibility analysis shows that a resolution of 10(-7)-10(-8) RIU is within reach over observation times of 1-30 s. The ultimate resolution is set only by intrinsic noise features of the cavity-based method, pointing to a potential limit below 10(-10) RIU/root Hz.