Realization of sucrose sensor using photonic waveguide: An application to biophotonics

A photonic waveguide sensor is explored in the present paper for effective sensing of sucrose concentration in an aqueous solution at a wavelength of 1550 nm by employing a 1-D photonic waveguide structure. The proposed structure comprises three layers, out of which odd layers are considered to be an InAs compound semiconductor having thickness of 700nm each whereas an even layer is air having thickness of 300 nm. Additionally, the effect of concentration variation of sucrose is theoretically examined with reference to reflected intensity, diffraction loss and transmitted intensity at the aforementioned waveguide. Reflected intensity from the said structure is computed through band gap analysis by a manipulating finite difference time domain (FDTD) technique, whereas diffraction loss and transmitted intensity are computed through numerical formulations. Further, simulation for diffraction loss with respect to different sucrose concentration has been carried out and interestingly the upshots revealed logarithmic deviation of diffraction efficiency with reference to variation in sucrose concentration from 10 gm/100ml to 70 gm/100ml. Apart from this, it is also revealed that there exists noteworthy shifts in both reflected as well as transmitted intensity with rise in sucrose concentration. Additionally, it is affirmed that both reflected light intensity and transmitted light intensity can be nicely fitted with a precise linear relationship having R2=0.998 and R2=0.9919 respectively, which claim an accurate sensing of sucrose concentration by using the proposed semiconductor based photonic waveguide and find applications in biophotonics.