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Competitive density waves in quasi-one-dimensional electron systems

Samuele Bissola·Alberto Parola
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Abstract

We investigate the nature of the ground state of the one-dimensional t-J model coupled to adiabatic phonons by use of the Lanczos technique at quarter filling. Due to the interplay between electron-electron and electron-phonon interactions, the model undergoes instabilities toward the formation of lattice and charge modulations. Moderate on-site and intra-site electron-phonon couplings lead to a competition of different spin-Peierls and dimerized states. In the former case two electrons belong to the unit cell and we expect a paramagnetic band insulator state, while lattice dimerization leads to a Mott insulating state with quasi long range antiferromagnetic order. The zero temperature phase diagram is obtained as a function of intra-site and inter-site electron-phonon couplings, analytically in the $J\to 0$ limit and numerically at finite J/t.

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Samuele Bissola, Alberto Parola. 2006-05-03. Competitive density waves in quasi-one-dimensional electron systems. https://doi.org/10.1103/physrevb.73.195108

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