We present a general method for the calculation of the energy band structure for a one-dimensional Kronig-Penney potential in the presence of a strong laser field. Numerical illustrations show that the energy band structure is strongly modified by the intense radiation field. In particular, it is also shown that the laser field creates new laser-induced forbidden gaps, widths of which increase with increasing intensity of radiation
We develop the concept of scattering matrix and we use it to perform stable numerical calculations of resonant tunneling of electrons through a multiple potential barrier in a semiconductor heterostructure. Electrons move in two external nonperturbative electric fields: constant and oscillating in time. We apply our algorithm for different strengths and spatial configurations of the fields.