influence of design parameters on multilayered nanoplasmonic structures in modified kretschmann-raether configurations

Surface plasmon resonance (spr) technique has been of recent interest in many fields such as biological and chemical sensing, defense-related applications, etc. the introduction of graphene sheet (metal-like optical properties) over a thin-film layers plays a significant role in generating spr. different nanoplasmonic structures like coupled waveguide spr (cwspr) and long range spr (lrspr) are considered with modified kretschmann-raether configurations for different wavelengths in visible range for plasmonic sensors application. characteristic transfer matrix (ctm) method in matlab environment is employed to obtain the theoretical results of lrspr-based nanoplasmonic structures. based on different compositions, minimum reflectivity as obtained is reported here. due to the incorporation of additional graphene thin layer, keeping the angle of incidence constant, the percentage of reflectivity is being increased significantly, thereby reducing the transmission within the layers. with the variation of thickness, refractive index of different layers as well as wavelength of the laser source, one optimize the structures to obtain best possible performance.