Dual-parameter sensor using low-index polymer-overlaid micro-resonator based on dispersion relation

A low-index polymer-overlaid micro-resonator (LIMR) with high sensitivity is investigated for simultaneous temperature and ambient refractive index (ARI) measurement. The sensitivity of the proposed LIMR to the ambient index is remarkably enhanced at the turning points of the dispersion curve. After examining the optical spectrum of the proposed LIMR sensor, we assess two typical configurations formed at the output of the fiber, fast-varying resonator (FVR) and slow-varying interferometer (SVI). The dual parameter sensing probe measures simultaneously, showing a presentation of temperature and ARI with the experimental sensing proportions of 0.30 nm/°C and 304 nm/RIU to FVR, 1.16 nm/°C and 1874 nm/RIU analogously to SVI. Therefore, it is possible to successfully discriminate temperature and ARI sensitivities by measuring different wavelength shifts of the proposed LIMR based on calculated dispersion curve.