Tunneling and current characteristics of two-miniband superlattice

Electron tunneling in semiconductor superlattices with asymmetric unit cells is studied in the two-miniband approximation. It is shown that the probability of interminiband tunneling through a superlattice period is independent of the initial quasi-momentum and can take minimum values in weak electric fields under conditions of the “anticrossing” of Wannier-Stark ladders. In the same fields, currents are at maximum. The dependences of the probability of interminiband tunneling and current on the field direction are predicted. The role of the diagonal elements of the coordinate operator is determined.