Defect mode tunability for escherichia coli in one-dimensional photonic crystals with thin graphene layers

Abstract

In this work, the transmittance spectrum for a defective one-dimensional photonic crystal was calculated. The crystal was composed of alternating GaAs and SiO2 layers, and its cavity was infiltrated by escherichia coli bacteria, which was surrounded by thin graphene layers. In this study, we assumed that the GaAs dielectric constant depends on the pressure applied. Within the photonic bandgap, a defect mode that tunes to decreasing wavelengths, as pressure increases can be observed. This shift in the transmittance spectrum is coupled with a decrease in the energy stored within the cavity. In addition, when the graphene-layer thickness was increased while maintaining the pressure constant at 0 GPa, the defect mode is tuned to a long wavelength, which favors two confined modes for thicknesses more than 33 nm.