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arXiv · 1511.00380

Effect of site dilution in the two-dimensional attractive Hubbard model

Saurabh Pradhan·G. Venketeswara Pai
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Abstract

We study the percolative superconducting transition as the density of randomly placed attractive centers grows in a host metal. Employing the Hubbard-Stratanovich transformation for the interaction and allowing for spatial, thermal fluctuations of the pairing field, we obtain real-space features of the transition from weak to strong coupling. Spectral and transport properties are studied in detail. BCS-BEC crossover is discussed in the context of site dilution of attractive centers.

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Saurabh Pradhan, G. Venketeswara Pai. 2015-11-02. Effect of site dilution in the two-dimensional attractive Hubbard model. https://doi.org/10.1103/physrevb.98.165142

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