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arXiv · 1106.4439

Narrowing of topological bands due to electronic orbital degrees of freedom

Jörn W. F. Venderbos·Maria Daghofer·Jeroen van den Brink
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Abstract

The Fractional Quantum Hall (FQH) effect has been predicted to occur in absence of magnetic fields and at high temperature in lattice systems that have flat bands with non-zero Chern number. We demonstrate that the presence of orbital degrees of freedom in frustrated lattice systems leads to a narrowing of topologically nontrivial bands. This robust effect does not rely on a fine-tuning of long-range hopping parameters as do other recent proposals to realize lattice FQH states and is directly relevant to a wide class of transition metal compounds.

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Jörn W. F. Venderbos, Maria Daghofer, Jeroen van den Brink. 2011-09-12. Narrowing of topological bands due to electronic orbital degrees of freedom. https://doi.org/10.1103/physrevlett.107.116401

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