ABSTRACT

An ultra-wide dynamic range fiber-optic surface plasmon resonance sensor based on phase interrogation is reported. The sensing head is based on a side-polished Polarization-Maintaining optical Fiber (PMF) with the configuration of Coupled Plasmon Waveguide Resonance (CPWR). The phase detection is accomplished by performing interference between the TE mode in sensing channel and TM mode in reference channel. The dynamic range of the sample’s refractive index has been extended to 0.444 in terms of Refractive Index Units (RIU), and the resolution on average is 3.43 × 10−7 RIU.