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Current-current correlations in a CuO_3 model system

Bhargavi Srinivasan·Marie-Bernadette Lepetit
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Abstract

We study a 3-band extended Hubbard model on a CuO_3 system by the density matrix renormalization group (DMRG) method. Our system has geometry similar to that of a section of the CuO_2 plane of the copper-oxide superconductors. We have studied the effects of nearest-neighbour repulsions on the current-current correlations of two model CuO_3 systems. We show that repulsive interactions are clearly capable of increasing the magnitude of the current-current correlations in both models studied. The long-distance behavior of the current-current correlations is qualitatively influenced by V. We show that repulsive interactions are capable of enhancing correlations involving at least one copper-oxygen rung over distances comparable to the length of the system. In some cases, V decreases the exponent corresponding to the power-law decay, leading to a considerable slowing down of the long-distance decay of the current-current correlations, compared to that of the Hubbard model.

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Bhargavi Srinivasan, Marie-Bernadette Lepetit. 2002-07-24. Current-current correlations in a CuO_3 model system. https://doi.org/10.1103/physrevb.66.024421

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