The absence of the absolutely continuousspectrum
نویسنده
چکیده
A modiication of the Kronig{Penney model consisting of equidistantly spaced 0 {interactions is considered. We prove that absolutely continuous spectrum of such a system disappears under innuence of an external electric eld. The result extends to periodic lattices of non{identical 0 interactions and potentials whose behavior, up to a bounded term, is powerlike with a power 1 on the decreasing side.
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تاریخ انتشار 1995