Relativistic surface states of a semi-infinite chain acted on by an electric field

Abstract In this paper, we deal with the relativistic effect of surface states of a semi-infinite chain of the Kronig-Penney type potential acted on by an electric field. The crux of the problem is to solve Dirac equation with a linear potential. Combining the solution with other solutions in the various regions, known through the boundary conditions, we get a relativistic expression for energy of surface states. The form is similar to that obtained in the absence of an electric field, which the expression automatically approaches as the field vanishes.