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arXiv · 1209.0049

Determinant Quantum Monte Carlo Study of the Enhancement of d-wave Pairing by Charge Inhomogeneity

R. Mondaini·T. Ying·T. Paiva·R. T. Scalettar
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Abstract

Striped phases, in which spin, charge, and pairing correlations vary inhomogeneously in the CuO_2 planes, are a known experimental feature of cuprate superconductors, and are also found in a variety of numerical treatments of the two dimensional Hubbard Hamiltonian. In this paper we use determinant Quantum Monte Carlo to show that if a stripe density pattern is imposed on the model, the d-wave pairing vertex is significantly enhanced. We attribute this enhancement to an increase in antiferromagnetic order which is caused by the appearence of more nearly half-filled regions when the doped holes are confined to the stripes. We also observe a π-phase shift in the magnetic order.

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R. Mondaini, T. Ying, T. Paiva, R. T. Scalettar. 2012-11-07. Determinant Quantum Monte Carlo Study of the Enhancement of d-wave Pairing by Charge Inhomogeneity. https://doi.org/10.1103/physrevb.86.184506

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