Metal - insulator transition for the almost Mathieu operator
نویسنده
چکیده
We prove that for Diophantine ω and almost every θ, the almost Mathieu operator, (Hω,λ,θΨ)(n) = Ψ(n+ 1) + Ψ(n− 1) +λ cos 2π(ωn+ θ)Ψ(n), exhibits localization for λ > 2 and purely absolutely continuous spectrum for λ < 2. This completes the proof of (a correct version of) the Aubry-André conjecture.
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تاریخ انتشار 1999