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arXiv · 1706.06135

Localization for the one-dimensional Anderson model via positivity and large deviations for the Lyapunov exponent

Valmir Bucaj·David Damanik·Jake Fillman·Vitaly Gerbuz·Tom VandenBoom·Fengpeng Wang·Zhenghe Zhang
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Abstract

We provide a complete and self-contained proof of spectral and dynamical localization for the one-dimensional Anderson model, starting from the positivity of the Lyapunov exponent provided by F\"urstenberg's theorem. That is, a Schr\"odinger operator in $\ell^2(\mathbb{Z})$ whose potential is given by independent identically distributed (i.i.d.) random variables almost surely has pure point spectrum with exponentially decaying eigenfunctions and its unitary group exhibits exponential off-diagonal decay, uniformly in time. This is achieved by way of a new result: for the Anderson model, one typically has Lyapunov behavior for all generalized eigenfunctions. We also explain how to obtain analogous statements for extended CMV matrices whose Verblunsky coefficients are i.i.d., as well as for half-line analogs of these models.

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Valmir Bucaj, David Damanik, Jake Fillman, Vitaly Gerbuz, Tom VandenBoom, Fengpeng Wang, Zhenghe Zhang. 2017-06-19. Localization for the one-dimensional Anderson model via positivity and large deviations for the Lyapunov exponent. https://arxiv.org/abs/1706.06135

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