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arXiv · 1102.0245

Finite energy spectral function of an anisotropic 2D system of coupled Hubbard chains

P. Ribeiro·P. D. Sacramento·K. Penc
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Abstract

We study the crossover from the one-dimensional to the two-dimensional Hubbard model in the photoemission spectra of weakly coupled chains. The chains with on-site repulsion are treated using the spin-charge factorized wave function, that is known to provide an essentially exact description of the chain in the strong coupling limit. The hoppings between the chains are considered as a perturbation. We calculate the dynamical spectral function at all energies in the random-phase approximation, by resuming an infinite set of diagrams. Even though the hoppings drive the system from a fractionalized Luttinger-liquid-like system to a Fermi-liquid-like system at low energies, significant characteristics of the one-dimensional system remain in the two-dimensional system. Furthermore, we find that introducing (frustrating) hoppings beyond the nearest neighbor one, the interference effects increase the energy and momentum range of the one--dimensional character.

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P. Ribeiro, P. D. Sacramento, K. Penc. 2011-02-01. Finite energy spectral function of an anisotropic 2D system of coupled Hubbard chains. https://doi.org/10.1103/physrevb.84.045112

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