Enhanced sensing performance of tapered profile in the apodized fiber Bragg grating for detection of cancerous cells utilizing their refractive index

Abstract

Tapered profiles are introduced in Bessel and Blackman apodized fiber Bragg grating, and their sensing performance is theoretically estimated. Reflectivity equation of proposed apodized tapered profiles is obtained using transfer matrix method and coupled mode theory. Since the effective refractive index of proposed waveguides varies with core radius therefore amplitude distribution and penetration depth of light in surrounding are modified. It is found that exponential tapered profile with Bessel apodization shows higher sensitivity 682.5 nm/RIU, detection accuracy 3858.45, and quality parameter 1718.02 /RIU with minimum FWHM 0.3972 nm of the reflection spectra. Spectral response of the tapered fiber Bragg grating is also analyzed through group delay study. Again, exponential profile was found to be particularly effective, producing less group delay ripples 2.98 ps and is maximum slope of 42.43 degree. Hence, exponential tapered profile is demonstrated for detection of cancer cells lies between the refractive index of 1.3333 to 1.4412.This article is protected by copyright. All rights reserved.