Influence of temperature on the sensitivity and signal-to-noise ratio of a fiber-optic surface-plasmon resonance sensor.

We have theoretically analyzed the influence of temperature on the performance of a fiber-optic sensor based on surface-plasmon resonance (SPR). The performance of the sensor has been evaluated in terms of its sensitivity and signal-to-noise ratio (SNR). The theoretical model for temperature dependence includes the thermo-optic effect in the fiber core and sensing layer, and phonon-electron scattering along with electron-electron scattering in the metal layer. The effect of temperature on the SNR and the sensitivity of the sensor with two different metals has been compared. The same comparison is carried out for the sensing layers with positive and negative thermo-optic coefficients. The theoretical model has been analyzed for both the nonremote and remote sensing cases. This detailed analysis of temperature-dependent SNR and sensitivity leads to achieving the best possible performance from a fiber-optic SPR sensor against the temperature variation.