Structure fits the purpose: photonic crystal fibers for evanescent-field surface-enhanced Raman spectroscopy

We report numerical simulation and hyperspectral Raman imaging of three index-guiding solid-core photonic crystal fibers (PCFs) of different air-cladding microstructures to assess their respective potential for evanescent-field Raman spectroscopy, with an emphasis on achieving surface-enhanced Raman scattering (SERS) over the entire fiber length. Suspended-core PCF consisting of a silica core surrounded by three large air channels conjoined by a thin silica web is the most robust of the three SERS-active PCFs, with a demonstrated detection sensitivity of 1 x 10(-10) M R6G in an aqueous solution of only similar to 7.3 mu L sampling volume. (C) 2010 Optical Society of America