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Landau-Zener Tunnelling in Waveguide Arrays

Ramaz Khomeriki·Stefano Ruffo
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Abstract

Landau-Zener tunnelling is discussed in connection with optical waveguide arrays. Light injected in a specific band of the Bloch spectrum in the propagation constant can be transmitted to another band, changing its physical properties. This is achieved using two waveguide arrays with different refractive indices, which amounts to consider a Schrödinger equation in a periodic potential with a step. The step causes wave "acceleration" and thus induces Landau-Zener tunnelling. The region of physical parameters where this phenomenon can occur is analytically determined and a realistic experimental setup is suggested. Its application could allow the realization of light filters.

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BibTeXRIS

Ramaz Khomeriki, Stefano Ruffo. 2004-08-06. Landau-Zener Tunnelling in Waveguide Arrays. https://doi.org/10.1103/physrevlett.94.113904

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