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arXiv · 1303.4541

Rientrant metallicity in the Hubbard model: the case of honeycomb nanoribbons

Franca Manghi·Francesco Petocchi
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Abstract

Based on the Cluster Perturbation solution of the Hubbard hamiltonian for a 2-D honeycomb lattice we present quasiparticle band structures of nanoribbons at half filling as a function of the on-site electron-electron repulsion. We show that at moderate values of e-e interaction ribbons with armachair shaped edges exhibit an unexpected semimetallic behavior, recovering the original insulating character only at larger values of $U$.

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Franca Manghi, Francesco Petocchi. 2013-03-19. Rientrant metallicity in the Hubbard model: the case of honeycomb nanoribbons. https://doi.org/10.1088/0031-8949%2F89%2F7%2F075802

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