Figure 7.

Propagation analysis in the proposed MZI biosensor, based on double monolayer of graphene capacitor. (a) Transmission response where the phase shift is evaluated as a function of the variation of the length of the sensing area ($L_{sens}$) at 800 nm wavelength and 1.33 refractive index in the cladding (b) Transmission response where the phase shift is evaluated as a function of the wavelength variation between 400 nm and 900 nm, for 1.24 cm length in the sensing area. (c) Close-view of the redshifted normalized transmission in the region where the maximum phase shift occurs, for refractive indices between 1.33 and 1.38 with a step of 0.01 RIU. (d) Sensitivity obtained through a linear regression calculated on the simulations carried out in (c).