Investigation of optical properties of gapped monolayer graphene under magnetic field with nearest and next-nearest-neighbor effects

This study investigates the optical properties of gapped monolayer graphene under an external magnetic field, focusing on optical absorption characteristics. A tight-binding model with nearest-neighbor and next-nearest-neighbor interactions is employed to study the light absorption behavior of graphene. We use linear response theory to determine the optical response by connecting electrical conductivity, the dielectric function, and optical absorption. To obtain an explicit expression for optical absorption, we apply the Green’s function technique to compute the current–current correlation function. This study elucidates how parameters such as chemical potential, magnetic field strength, energy gap size, and next-nearest-neighbor hopping amplitude influence graphene’s optical absorption across a range of frequencies. The findings enhance our understanding of this remarkable material and provide new insights into its potential for advanced technological applications.