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arXiv · 0811.0742

Quantum phase transition in a 1D transport model with boson affected hopping: Luttinger liquid versus charge-density-wave behavior

S. Ejima·G. Hager·H. Fehske
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Abstract

We solve a very general two-channel fermion-boson model describing charge transport within some background medium by means of a refined pseudo-site density matrix renormalization group (DMRG) technique. Performing a careful finite-size scaling analysis, we determine the ground-state phase diagram and convincingly prove that the model exhibits a metal-insulator quantum phase transition for the half-filled band case. In order to characterize the metallic and insulating regimes we calculate besides the local particle densities and fermion-boson correlation functions, the kinetic energy, the charge structure factor, the Luttinger liquid charge exponent and the single-particle excitation gap for a one-dimensional infinite system.

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S. Ejima, G. Hager, H. Fehske. 2009-02-10. Quantum phase transition in a 1D transport model with boson affected hopping: Luttinger liquid versus charge-density-wave behavior. https://doi.org/10.1103/physrevlett.102.106404

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