Vol. 42, Issue 3, pp. 493-501 (2012)

Abstract

A surface-plasmon-resonance (SPR) sensor based on photonic-crystal-fiber (PCF) with large size microfluidic channels is proposed. The size of the microfluidic channels with gold coating can be enlarged by reducing the number of the holes in the second layer, so the structure of the PCF is simple and easy to manufacture. It is propitious for metal coating and infiltration of microfluidic. The contact area of sample and metal film is increased, and the interface is closer to the core, so the energy coupling between the plasmon mode and the core-guided mode is easier. Numerical results indicate that the excitation of the plasmon mode is sensitive to the change of the refractive index of adjacent analyte. Sensitivity of the sensor is comparable to the ones of the best existing waveguide sensors. The amplitude resolution is demonstrated to be as low as 3.3×10^–5 RIU, and the spectral resolution is 5×10^–6 RIU (where RIU means the refractive index unit). The refractive index of microfluidic can be measured effectively.