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arXiv · 1108.0777

Sharp trace asymptotics for a class of 2D-magnetic operators

Horia D. Cornean·Soren Fournais·Rupert Frank·Bernard Helffer
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Abstract

In this paper we prove a two-term asymptotic formula for for the spectral counting function for a 2D magnetic Schrödinger operator on a domain (with Dirichlet boundary conditions) in a semiclassical limit and with strong magnetic field. By scaling, this is equivalent to a thermodynamic limit of a 2D Fermi gas submitted to a constant external magnetic field. The original motivation comes from a paper by H. Kunz in which he studied, among other things, the boundary correction for the grand-canonical pressure and density of such a Fermi gas. Our main theorem yields a rigorous proof of the formulas announced by Kunz. Moreover, the same theorem provides several other results on the integrated density of states for operators of the type $(-ih\nabla- μ{\bf A})^2$ in $L^2(Ω)$ with Dirichlet boundary conditions.

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Horia D. Cornean, Soren Fournais, Rupert Frank, Bernard Helffer. 2011-08-03. Sharp trace asymptotics for a class of 2D-magnetic operators. https://arxiv.org/abs/1108.0777

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