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arXiv · 1309.6873

Charge-density-wave formation in the Edwards fermion-boson model at one-third band filling

Satoshi Ejima·Holger Fehske
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Abstract

We examine the ground-state properties of the one-dimensional Edwards spinless fermion transport model by means of large-scale density-matrix renormalization-group calculations. Determining the single-particle gap and the Tomonaga-Luttinger liquid parameter ($K_\rho$) at zero temperature, we prove the existence of a metal-to-insulator quantum phase transition at one-third band filling. The insulator---established by strong correlation in the background medium---typifies a charge density wave (CDW) that is commensurate with the band filling. $K_\rho=2/9$ is very small at the quantum critical point, and becomes $K_\rho^{\rm CDW}=1/9$ in the infinitesimally doped three-period CDW, as predicted by the bosonization approach.

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Satoshi Ejima, Holger Fehske. 2013-09-26. Charge-density-wave formation in the Edwards fermion-boson model at one-third band filling. https://doi.org/10.7566/jpscp.3.013006

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