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arXiv · 2411.14171

A rigorous Peierls-Onsager effective dynamics for semimetals in long-range magnetic fields

Horia D. Cornean·Bernard Helffer·Radu Purice
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Abstract

We consider periodic (pseudo)differential {elliptic operators of Schr\"odinger type} perturbed by weak magnetic fields not vanishing at infinity, and extend our previous analysis in \cite{CIP,CHP-2,CHP-4} to the case {of a semimetal having a finite family of Bloch eigenvalues whose range may overlap with the other Bloch bands but remains isolated at each fixed quasi-momentum.} We do not make any assumption of triviality for the associated Bloch bundle. In this setting, we formulate a general form of the Peierls-Onsager substitution {via strongly localized tight-frames and magnetic matrices. We also} prove the existence of an approximate time evolution for initial states supported inside the range of the isolated Bloch family, with a precise error control.

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Horia D. Cornean, Bernard Helffer, Radu Purice. 2024-11-21. A rigorous Peierls-Onsager effective dynamics for semimetals in long-range magnetic fields. https://arxiv.org/abs/2411.14171

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