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arXiv · 1412.6342

Observation of a localized flat-band state in a photonic Lieb lattice

Sebabrata Mukherjee·Alexander Spracklen·Debaditya Choudhury·Nathan Goldman·Patrik Öhberg·Erika Andersson·Robert R. Thomson
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Abstract

We show experimentally how a non-diffracting state can be excited in a photonic Lieb lattice. This lattice supports three energy bands, including a perfectly flat middle band, which corresponds to an infinite effective mass with zero dispersion. We show that a suitable optical input state can be prepared so as to only excite the flat band. We analyse, both experimentally and theoretically, the evolution of such photonic flat-band states, and show their remarkable robustness, even in the presence of disorder.

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Sebabrata Mukherjee, Alexander Spracklen, Debaditya Choudhury, Nathan Goldman, Patrik Öhberg, Erika Andersson, Robert R. Thomson. 2015-05-15. Observation of a localized flat-band state in a photonic Lieb lattice. https://doi.org/10.1103/physrevlett.114.245504

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