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arXiv · 1006.2330

Microscopic Inhomogeneity and Superconducting Properties of a Two-dimensional Hubbard Model for High-$T_c$ Cuprate

Satoshi Okamoto·Thomas A. Maier
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Abstract

Recent scanning tunneling microscopy measurements on cuprate superconductors have revealed remarkable spatial inhomogeneities in the single-particle energy gap. Using cellular dynamical mean-field theory, we study the zero temperature superconducting properties of a single-band Hubbard model with a spatial modulation of the electron density. We find that the inhomogeneity in the electronic structure results in a substantial spatial variation in the superconducting order parameter and single-particle energy gap, reminiscent of the experimental results. In particular, we find that the order parameter and gap amplitudes in the hole-rich regions are significantly enhanced over the corresponding quantities in a uniform system, if the hole-rich regions are embedded in regions with smaller hole density.

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Satoshi Okamoto, Thomas A. Maier. 2010-06-11. Microscopic Inhomogeneity and Superconducting Properties of a Two-dimensional Hubbard Model for High-$T_c$ Cuprate. https://doi.org/10.1103/physrevb.81.214525

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