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Bounds on the spectral shift function and the density of states

Dirk Hundertmark·Rowan Killip·Shu Nakamura·Peter Stollmann·Ivan Veselic'
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Abstract

We study spectra of Schrödinger operators on $\RR^d$. First we consider a pair of operators which differ by a compactly supported potential, as well as the corresponding semigroups. We prove almost exponential decay of the singular values $μ_n$ of the difference of the semigroups as $n\to \infty$ and deduce bounds on the spectral shift function of the pair of operators. Thereafter we consider alloy type random Schrödinger operators. The single site potential $u$ is assumed to be non-negative and of compact support. The distributions of the random coupling constants are assumed to be Hölder continuous. Based on the estimates for the spectral shift function, we prove a Wegner estimate which implies Hölder continuity of the integrated density of states.

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Dirk Hundertmark, Rowan Killip, Shu Nakamura, Peter Stollmann, Ivan Veselic'. 2004-12-21. Bounds on the spectral shift function and the density of states. https://doi.org/10.1007/s00220-005-1460-0

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