Transfer Matrix for Multilayer Structure

A transfer matrix which transfers the electron states from one side of the interface to the other is defined for crystalline multilayer with layers joined coherently. The total transfer matrix for several sequential interfaces can be simply obtained by multiplication of the matrices. The bound states as well as the extended states can be naturally described in terms of transfer matrix. As an illustration of using transfer matrix, the equation of quantum well states for sandwich structure have been given in this way.