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arXiv · 1710.00899

Wegner estimate and disorder dependence for alloy-type Hamiltonians with bounded magnetic potential

Matthias Täufer·Martin Tautenhahn
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Abstract

We consider non-ergodic magnetic random Sch\"odinger operators with a bounded magnetic vector potential. We prove an optimal Wegner estimate valid at all energies. The proof is an adaptation of the arguments from [Kle13], combined with a recent quantitative unique continuation estimate for eigenfunctions of elliptic operators from [BTV15]. This generalizes Klein's result to operators with a bounded magnetic vector potential. Moreover, we study the dependence of the Wegner-constant on the disorder parameter. In particular, we show that above the model-dependent threshold $E_0(\infty) \in (0, \infty]$, it is impossible that the Wegner-constant tends to zero if the disorder increases. This result is new even for the standard (ergodic) Anderson Hamiltonian with vanishing magnetic field.

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Matthias Täufer, Martin Tautenhahn. 2017-10-02. Wegner estimate and disorder dependence for alloy-type Hamiltonians with bounded magnetic potential. https://doi.org/10.1007/s00023-017-0640-8

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