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arXiv · 1205.5457

Expansion of a wave-packet in lattices with disorder and nonlinearity

Uta Naether·Santiago Rojas-Rojas·Alejandro J. Martinez·Simon Sützer·Andreas Tünnermann·Stefan Nolte·Mario I. Molina·Rodrigo A. Vicencio·Alexander Szameit
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Abstract

We show, theoretically and experimentally, the counterintuitive result that an increase of disorder can result in an enhanced spreading of an initially localized excitation. Moreover, we find that adding a focusing nonlinearity facilitates the expansion of the wave-packet even further by increasing its effective size. We find a clear transition between between the regions of enhanced spreading (weak disorder) and localization (strong localization) described by a "diffusion peak".

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Uta Naether, Santiago Rojas-Rojas, Alejandro J. Martinez, Simon Sützer, Andreas Tünnermann, Stefan Nolte, Mario I. Molina, Rodrigo A. Vicencio, Alexander Szameit. 2012-05-24. Expansion of a wave-packet in lattices with disorder and nonlinearity. https://doi.org/10.1364/oe.21.000927

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