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arXiv · 1302.2449

Structure-dynamics relationship in coherent transport through disordered systems

Stefano Mostarda·Federico Levi·Diego Prada-Gracia·Florian Mintert·Francesco Rao
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Abstract

Quantum transport is strongly influenced by interference with phase relations that depend sensitively on the scattering medium. Since even small changes in the geometry of the medium can turn constructive interference to destructive, a clear relation between structure and fast, efficient transport is difficult to identify. Here we present a complex network analysis of quantum transport through disordered systems to elucidate the relationship between transport efficiency and structural organization. Evidence is provided for the emergence of structural classes with different geometries but similar high efficiency. Specifically, a structural motif characterised by pair sites which are not actively participating to the dynamics renders transport properties robust against perturbations. Our results pave the way for a systematic rationalization of the design principles behind highly efficient transport which is of paramount importance for technological applications as well as to address transport robustness in natural light harvesting complexes.

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Stefano Mostarda, Federico Levi, Diego Prada-Gracia, Florian Mintert, Francesco Rao. 2013-02-11. Structure-dynamics relationship in coherent transport through disordered systems. https://doi.org/10.1038/ncomms3296

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