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Ising transition in a one-dimensional quarter-filled electron system with dimerization

M. Tsuchiizu·E. Orignac
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Abstract

We examine critical properties of the quarter-filled one-dimensional Hubbard model with dimerization and with the onsite and nearest-neighbor Coulomb repulsion U and V. By utilizing the bosonization method, it is shown that the system exhibits an Ising quantum phase transition from the Mott insulating state to the charge-ordered insulating state. It is also shown that the dielectric permittivity exhibits a strong enhancement as decreasing temperature with power-law dependence at the Ising critical point.

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M. Tsuchiizu, E. Orignac. 2001-10-16. Ising transition in a one-dimensional quarter-filled electron system with dimerization. https://doi.org/10.1016/s0022-3697(02)00014-8

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