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Power laws in a 2-leg ladder of interacting spinless fermions

L. G. Caron·C. Bourbonnais
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Abstract

We use the Density-Matrix Renormalization Group to study the single-particle and two-particle correlation functions of spinless fermions in the ground state of a quarter-filled ladder. This ladder consists of two chains having an in-chain extended Coulomb interaction reaching to third neighbor and coupled by inter-chain hopping. Within our short numerical coherence lengths, typically reaching ten to twenty sites, we find a strong renormalization of the interchain hopping and the existence of a dimensional crossover at smaller interactions. We also find power exponents for single-particle hopping and interchain polarization consistent with the single chain. The total charge correlation function has a larger power exponent and shows signs of a crossover from incoherent fermion hopping to coherent particle-hole pair motion between chains. There are no significant excitation energies.

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L. G. Caron, C. Bourbonnais. 2001-12-05. Power laws in a 2-leg ladder of interacting spinless fermions. https://doi.org/10.1103/physrevb.66.045101

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