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arXiv · 0711.3075

Dimensional tuning of electronic states under strong and frustrated interactions

Chisa Hotta·Frank Pollmann
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Abstract

We study a model of strongly interacting spinless fermions on an anisotropic triangular lattice. At half-filling and the limit of strong repulsive nearest-neighbor interactions, the fermions align in stripes and form an insulating state. When a particle is doped, it either follows a one-dimensional free motion along the stripes or fractionalizes perpendicular to the stripes. The two propagations yield a dimensional tuning of the electronic state. We study the stability of this phase and derive an effective model to describe the low-energy excitations. Spectral functions are presented which can be used to experimentally detect signatures of the charge excitations.

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Chisa Hotta, Frank Pollmann. 2008-04-21. Dimensional tuning of electronic states under strong and frustrated interactions. https://doi.org/10.1103/physrevlett.100.186404

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