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arXiv · 1510.07900

Direct measurement of second-order coupling in a waveguide lattice

Robert Keil·Benedikt Pressl·René Heilmann·Markus Gräfe·Gregor Weihs·Alexander Szameit
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Abstract

We measure the next-nearest-neighbour coupling in an array of coupled optical waveguides directly via an integrated eigenmode interferometer. In contrast to light propagation experiments, the technique is insensitive to nearest-neighbour dynamics. Our results show that second-order coupling in a linear configuration can be suppressed well below the level expected from the exponential decay of the guided modes.

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Robert Keil, Benedikt Pressl, René Heilmann, Markus Gräfe, Gregor Weihs, Alexander Szameit. 2015-12-02. Direct measurement of second-order coupling in a waveguide lattice. https://doi.org/10.1063/1.4937807

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