Analyzing spectral properties and sensing performance of multi-single-multi mode fiber combination

Abstract

Here, we have executed a comprehensive investigation on the impact of the single-mode fiber (SMF) lengths on the sensing performance of multi-single-multi mode (MSM) fiber segment combination under different external parameters including temperature, strain and refractive index. An experimental setup is proposed to demonstrate the efficacy in measuring the aforementioned variables with larger sensitivity along with the resolution over the large dynamic range. In addition, different phenomenal characteristics namely fast Fourier transform, fringe visibility, and the free spectral range of the observed transmission spectrum have also been analyzed meticulously. The achieved results show that the sensitivities increase with an increase of the SMF length and are restricted to 12 cm length due to the superimposing and less resolution of the probing dips beyond this. The highest sensitivities of 133.25 pm °C−1, −3.41 pm με −1 and −52.10 nm/RIU for temperature, strain and refractive index, respectively are achieved for the 12 cm length of the SMF which assures potential employment of the proposed sensor in various sensing applications.