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A dimerized spin fluid in a one-dimensional electron system

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

The ground state of a one-dimensional Hubbard model with a bond-charge attraction W term at half-filling is investigated by the density matrix renormalization group method. It is confirmed that the spin gap will be closed at U>8W. But the long-range bond order wave survives even when the spin gap is closed. It indicates that the ground state is a novel dimerized spin fluid at U>8W. By a charge-spin transformation, it is shown that there should be a dimerized metallic phase at U<-8W. Furthermore, it is found that the Hubbard interaction U enhances initially the dimerization for a weak bond charge attraction W whereas it reduces monotonously the dimerization for a stronger bond charge attraction W.

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Y. Z. Zhang, C. Q. Wu, H. Q. Lin. 2001-09-06. A dimerized spin fluid in a one-dimensional electron system. https://doi.org/10.1103/physrevb.65.115101

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