Finite Element Analysis of Nanowire Superlattice Structures

Finite Element calculations were performed on finite nanowire superlattice (NWSL) structures with a cylindrical cross section so as to determine electronic eigenstates and energy eigenvalues. In recent years, such structures have been grown as they are good candidates for use in active regions of future optoelectronic devices. In particular, we analyzed the qualitative differences in terms of wavefunctions and energy eigenvalues between structures containing the same number of barriers and wells (asymmetrical) and structures where the number of barrier layers is one above the number of well layers (symmetrical). Dirichlet boundary conditions were imposed on the surface of the nanowire structures corresponding to the case where the nanostructure environment is vacuum. We compared our results with those available for the Kronig-Penney model describing infinite NWSLs. Asymmetrical NWSL structures show qualitative and quantitative differences as compared to both symmetrical NWSL structures and infinite periodic NWSL structures.