Proposal for the detection of breast cancer at its early stage using wave-theory-based analysis in a tapered fiber structure illuminated by the Bessel–Gauss beam for enhanced sensitivity

Abstract

An analytical exploration of a fiber-optic biosensor with a tapered structure for the detection of breast cancer at its early stage by illuminating the Bessel–Gauss beam in a multilayer structure, using wave-theory-based technique, is proposed to acquire closer results between experimental and theoretical models. By using a Gaussian beam, the observed sensitivity is 2688.5 dB/RIU and 0.204 nm/ng/mL, where all the results are in good agreement with the experimental outcomes reported by Sun et al. [Opt. Commun. 463, 125375 (2020)10.1016/j.optcom.2020.125375]. Thus, this proposed theory is experimentally validated. Now, this tapered theoretical analysis is further extended utilizing the Bessel–Gauss beam, where for the first time, to the best of our knowledge, the discerned sensitivity is enhanced to 14,979.8 dB/RIU and 0.33 nm/ng/mL with a resolution of 6. 68 × 1 0 − 7 , which is 6.59 times superior to the reported results to date. Higher spectral shifts are noticed using the wavelength interrogation technique for the concentration of (2–15) ng/mL of HER2 biological marker. Thus improvement in sensitivity and resolution at lower concentrations is achieved, which indicates the proposed idea for the identification of breast cancer at its early stage.