Four-Layer Graphene System’s Optical Conductivity with Compose mono-mono-mono-mono , at Different Broadening Widths

Four-layer graphene system’s longitudinal optical conductivity by changing the broadening widths at fixed electron densities in different layers, has been studied in this paper. In this study we’ve chosen all the layers to be mono-layer graphene. Each layer, has been separated by a dielectric material, with thickness about ten nanometers. The electron densities in each layer can be tuned by changing gate voltage. By using a MATLAB program, the data has been collected and processed theoretically and numerically. Using dielectric and electron density-density correlation tensors, the imaginary part of dielectric function for mono-mono-mono-mono graphene system is calculated, and optical conductivities are plotted as a function of photon energies in different broadening widths, and fixed electron densities. The interpreted results show that changing broadening widths has considerable affect on longitudinal optical conductivity.