Microstructured and Photonic Bandgap Fibers for Applications in the Resonant Bio- and Chemical Sensors
Figure 5
(a)Schematics of a MOF-based SPR sensor. The fiber comprises six air holes surrounding a solid fiber core. These holes form a microstructured cladding with low effective refractive index. A smaller hole is introduced in the core center to enable tunability of the core mode effective refractive index to facilitate phase matching with a plasmon. Two large semicircular metalized channels are integrated into the fiber structure to enable efficient microfluidic flow of analyte and plasmon excitation at the metal/analyte interface. (b) Dispersion relations of a core-guided-mode (thick solid line) and a surface plasmon (thick dashed line) in the vicinity of the phase matching point. Insets (I), (II) show energy fluxes of the core-guided and plasmon modes close to the phase matching point. Transmission loss of a core-guided-mode (thin solid line) exhibits strong increase at the phase matching point due to efficient mixing with a plasmon as confirmed by its energy flux distribution (inset (III)).
