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Study of the ionic Peierls-Hubbard model using density matrix renormalization group methods

Y. Z. Zhang·C. Q. Wu·H. Q. Lin
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Abstract

Density matrix renormalization group methods are used to investigate the quantum phase diagram of a one-dimensional half-filled ionic Hubbard model with bond-charge attraction, which can be mapped from the Su-Schrieffer-Heeger-type electron-phonon coupling at the antiadiabatic limit. A bond order wave (dimerized) phase which separates the band insulator from the Mott insulator always exists as long as electron-phonon coupling is present. This is qualitatively different from that at the adiabatic limit. Our results indicate that electron-electron interaction, ionic potential and quantum phonon fluctuations combine in the formation of the bond-order wave phase.

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Y. Z. Zhang, C. Q. Wu, H. Q. Lin. 2004-10-08. Study of the ionic Peierls-Hubbard model using density matrix renormalization group methods. https://doi.org/10.1103/physrevb.72.125126

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