Exposed core microstructured optical fiber surface plasmon resonance biosensor

Taming the Light in Microstructured Optical Fibers for Sensing

“…a) by thermal evaporation. This fiber possessed a significantly smaller core diameter (Ø core ~10 μm) compared to the bare core fibers previously used (Ø core ~140 μm) and resulted in a reduction of the resonance linewidth by a factor 3, while the refractive index sensitivity (δλ/δn) remained constant, improving the refractive index detection limit by the same factor.…”

D-shape polymer optical fibres for surface plasmon resonance sensing

“…Most probably, the reduction in the SPR resonance width in our sensors is caused by improved smoothness of the metal layer which was deposited on the flat fibre surface obtained by polishing the preform. For other SPR sensors made on multimode microstructured optical fibres with an exposed core, the res− onance FWHM was about 44 nm [26] and 77 nm [27] (see Table 2), but the SPR spectrum was additionally modulated due to intermodal interference, which obstructs precise mea− surements of the resonance wavelength.…”

“…26 and 27. A special fibre structure with a side−opened suspended core allowed for easy silver deposi− tion on the fibre core by thermal evaporation [26] while in Ref. 27 a silver layer was deposited by an electro−less plating method.…”

Surface plasmon scattering: an alternative approach for optical fibers biosensors

“…3 are particularly suited for this as they do not compromise between the core size and the mechanical strength, alleviating some fundamental limitations of fiber tapers. We have shown that using such MOF can significantly reduce the linewidth of the SPR signature in scattering mode from 150 nm for a 140 μm core fiber down to 50 nm for a 10 μm core diameter without jeopardizing the refractive index sensitivity [19] . Further size reduction of the fiber core is possible, enabling only few modes to remain and even single mode operation.…”

“…application has nd geometries high refractive geometry [19] e optical setup ource coupled sert in Fig. 1 …”