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Spectral microscopic mechanisms and quantum phase transitions in a 1D correlated problem

J. M. P. Carmelo·K. Penc
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Abstract

In this paper we study the dominant microscopic processes that generate nearly the whole one-electron removal and addition spectral weight of the one-dimensional Hubbard model for all values of the on-site repulsion $U$. We find that for the doped Mott-Hubbard insulator there is a competition between the microscopic processes that generate the one-electron upper-Hubbard band spectral-weight distributions of the Mott-Hubbard insulating phase and finite-doping-concentration metallic phase, respectively. The spectral-weight distributions generated by the non-perturbative processes studied here are shown elsewhere to agree quantitatively for the whole momentum and energy bandwidth with the peak dispersions observed by angle-resolved photoelectron spectroscopy in quasi-one-dimensional compounds.

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J. M. P. Carmelo, K. Penc. 2005-12-20. Spectral microscopic mechanisms and quantum phase transitions in a 1D correlated problem. https://doi.org/10.1088/0953-8984%2F18%2F10%2F011

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