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The one-dimensional t-J model coupled to adiabatic phonons: A numerical investigation

Samuele Bissola·Alberto Parola
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Abstract

The ground state of the one-dimensional t-J model coupled with phonons in the adiabatic limit is numerically investigated by use of the Lanczos technique at quarter filling. Due to the interplay between the electron-electron Coulomb repulsion and electron-phonon interaction, this model shows a sequence of lattice distortions leading to the formation of charge-density-waves and bond-order-waves. Moderate electron-electron and electron-lattice coupling may lead to coexistence of dimerization and tetramerization in the distortion pattern. Dimerization leads to the formation of an "antiferromagnetic" Mott insulator, while tetramerization gives rise to a spin-Peierls phase. By increasing the super-exchange coupling, antiferromagnetism is inhibited due to the change of the distortion periodicity.

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Samuele Bissola, Alberto Parola. 2004-09-22. The one-dimensional t-J model coupled to adiabatic phonons: A numerical investigation. https://doi.org/10.1103/physrevb.70.235116

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