We present a way of guiding light to planar surface-enhanced Raman scattering (SERS) substrates by using evanescent-wave coupling. Using nanostructured chalcogenide glass-based SERS substrates, we experimentally show the incident-angle dependence of plasmon resonances of the SERS substrates, demonstrating strong resonances at large incident angles. This allows the evanescent-wave excitation of SERS substrates through tapered optical fibers. Experiments show that fiber-taper-excited SERS substrates exhibit a significant enhancement of the Raman spectra of Rhodamine-6G analyte molecules. This configuration forms the basis of fiber-optic-based, reproducible, highly compact, and sensitive SERS systems.
© 2009 Optical Society of America
Original Manuscript: April 29, 2009
Revised Manuscript: June 28, 2009
Manuscript Accepted: July 29, 2009
Published: August 31, 2009
Vol. 4, Iss. 11 Virtual Journal for Biomedical Optics
Lei Su, T. H. Lee, and S. R. Elliott, "Evanescent-wave excitation of surface-enhanced Raman scattering substrates by an optical-fiber taper," Opt. Lett. 34, 2685-2687 (2009)