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Mott-Peierls Transition in the extended Peierls-Hubbard model

Eric Jeckelmann
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Abstract

The one-dimensional extended Peierls-Hubbard model is studied at several band fillings using the density matrix renormalization group method. Results show that the ground state evolves from a Mott-Peierls insulator with a correlation gap at half-filling to a soliton lattice with a small band gap away from half-filling. It is also confirmed that the ground state of the Peierls-Hubbard model undergoes a transition to a metallic state at finite doping. These results show that electronic correlations effects should be taken into account in theoretical studies of doped polyacetylene. They also show that a Mott-Peierls theory could explain the insulator-metal transition observed in this material.

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Eric Jeckelmann. 1997-11-25. Mott-Peierls Transition in the extended Peierls-Hubbard model. https://doi.org/10.1103/physrevb.57.11838

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