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arXiv · 1406.6293

Interaction created effective flat bands in conducting polymers

Zsolt Gulacsi
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Abstract

For a general class of conducting polymers with arbitrary large unit cell and different on-site Coulomb repulsion values on different type of sites, I demonstrate in exact terms the emergence possibility of an upper, interaction created "effective" flat band. This last appears as a consequence of a kinetic energy quench accompanied by a strong interaction energy decrease, and leads to a non-saturated ferromagnetic state. This ordered state clearly differs from the known flat-band ferromagnetism. This is because it emerges in a system without bare flat bands, requires inhomogeneous on-site Coulomb repulsions values, and possesses non-zero lower interaction limits at the emergence of the ordered phase.

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Zsolt Gulacsi. 2014-06-24. Interaction created effective flat bands in conducting polymers. https://doi.org/10.1140/epjb/e2014-50294-x

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