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Spectral Properties of Polyharmonic Operators with Limit-Periodic Potential in Dimension Two

Yulia Karpeshina·Young-Ran Lee
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Abstract

We consider a polyharmonic operator $H=(-Δ)^l+V(x)$ in dimension two with $l\geq 6$ and a limit-periodic potential $V(x)$. We prove that the spectrum of $H$ contains a semiaxis and there is a family of generalized eigenfunctions at every point of this semiaxis with the following properties. First, the eigenfunctions are close to plane waves $e^{i< \vec k,\vec x>}$ at the high energy region. Second, the isoenergetic curves in the space of momenta $\vec k$ corresponding to these eigenfunctions have a form of slightly distorted circles with holes (Cantor type structure).

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Yulia Karpeshina, Young-Ran Lee. 2006-01-04. Spectral Properties of Polyharmonic Operators with Limit-Periodic Potential in Dimension Two. https://arxiv.org/abs/math-ph/0601008

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