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arXiv · 1502.05010

Uniformly distributed eigenfunctions on tori with random impurities

Henrik Ueberschaer
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Abstract

We study a random Schroedinger operator, the Laplacian with N independently uniformly distributed random delta potentials on flat tori T^d_L = R^d/LZ^d, d = 2, 3, where L > 0 is large. We determine a condition in terms of the size of the torus L, the density of the potentials \rho = N/L^d and the energy of the eigenfunction E such any such eigenfunctions will with nonzero probability be uniformly distributed on the entire torus. We remark that the equidistribution we prove here is still consistent with a localized regime, where the localization length is much larger than the size of the torus. In fact our result implies a certain polynomial lower bound on the localization length, so the localization length becomes infinitely large as E tends to infinity.

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Henrik Ueberschaer. 2015-02-17. Uniformly distributed eigenfunctions on tori with random impurities. https://arxiv.org/abs/1502.05010

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