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arXiv · 1111.4549

Localization of two-dimensional massless Dirac fermions in a magnetic quantum dot

Martin Könenberg·Edgardo Stockmeyer
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Abstract

We consider a two-dimensional massless Dirac operator $H$ in the presence of a perturbed homogeneous magnetic field $B=B_0+b$ and a scalar electric potential $V$. For $V\in L_{\rm loc}^p(\R^2)$, $p\in(2,\infty]$, and $b\in L_{\rm loc}^q(\R^2)$, $q\in(1,\infty]$, both decaying at infinity, we show that states in the discrete spectrum of $H$ are superexponentially localized. We establish the existence of such states between the zeroth and the first Landau level assuming that V=0. In addition, under the condition that $b$ is rotationally symmetric and that $V$ satisfies certain analyticity condition on the angular variable, we show that states belonging to the discrete spectrum of $H$ are Gaussian-like localized.

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Martin Könenberg, Edgardo Stockmeyer. 2011-11-19. Localization of two-dimensional massless Dirac fermions in a magnetic quantum dot. https://arxiv.org/abs/1111.4549

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