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arXiv · 1512.09366

On quantum graph filters with flat passbands

Ondřej Turek
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Abstract

We examine transmission through a quantum graph vertex to which auxiliary edges with constant potentials are attached. We find a characterization of vertex couplings for which the transmission probability from a given "input" line to a given "output" line shows a flat passband. The bandwidth is controlled directly by the potential on the auxiliary edges. Vertices with such couplings can thus serve as controllable band-pass filters. The paper extends earlier works on the topic. The result also demonstrates the effectivity of the $ST$-form of boundary conditions for a study of scattering in quantum graph vertices.

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Ondřej Turek. 2015-12-31. On quantum graph filters with flat passbands. https://arxiv.org/abs/1512.09366

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