Destruction of tunneling in superlattices under the action of square-wave electric fields

Abstract

The problem of coherent motion of an electron in a long period superlattice driven by a square-wave electric field is studied. Exact solutions for the amplitude propagators, the field-induced polarization, the mean-square displacement, and the quasi-energy spectrum are obtained generally, from which the results for any special initial distribution and for any long range hopping coupling can be deduced. The field-induced destruction of tunneling is found to appear in the cases of the ratio of the field period to the Bloch period being an even number.