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arXiv · 1505.02347

On the existence of bound states in asymmetric leaky wires

Pavel Exner·Semjon Vugalter
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Abstract

We analyze spectral properties of a leaky wire model with a potential bias. It describes a two-dimensional quantum particle exposed to a potential consisting of two parts. One is an attractive $δ$-interaction supported by a non-straight, piecewise smooth curve $\mathcal{L}$ dividing the plane into two regions of which one, the `interior', is convex. The other interaction component is a constant positive potential $V_0$ in one of the regions. We show that in the critical case, $V_0=α^2$, the discrete spectrum is non-void if and only if the bias is supported in the interior. We also analyze the non-critical situations, in particular, we show that in the subcritical case, $V_0<α^2$, the system may have any finite number of bound states provided the angle between the asymptotes of $\mathcal{L}$ is small enough.

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Pavel Exner, Semjon Vugalter. 2015-05-10. On the existence of bound states in asymmetric leaky wires. https://doi.org/10.1063/1.4941139

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