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Persistence of Anderson localization in Schrödinger operators with decaying random potentials

Alexander Figotin·François Germinet·Abel Klein·Peter Müller
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Abstract

We show persistence of both Anderson and dynamical localization in Schrödinger operators with non-positive (attractive) random decaying potential. We consider an Anderson-type Schrödinger operator with a non-positive ergodic random potential, and multiply the random potential by a decaying envelope function. If the envelope function decays slower than $|x|^{-2}$ at infinity, we prove that the operator has infinitely many eigenvalues below zero. For envelopes decaying as $|x|^{-α}$ at infinity, we determine the number of bound states below a given energy $E<0$, asymptotically as $α\downarrow 0$. To show that bound states located at the bottom of the spectrum are related to the phenomenon of Anderson localization in the corresponding ergodic model, we prove: (a) these states are exponentially localized with a localization length that is uniform in the decay exponent $α$; (b)~ dynamical localization holds uniformly in $α$.

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Alexander Figotin, François Germinet, Abel Klein, Peter Müller. 2006-04-09. Persistence of Anderson localization in Schrödinger operators with decaying random potentials. https://doi.org/10.1007/s11512-006-0039-0

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