Coexistence of superconductivity and charge-density waves in a two-dimensional Holstein model at half-filling

S. Sykora; A. Hübsch; K. W. Becker

doi:10.1209/0295-5075/85/57003

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arXiv · 0808.4037

Coexistence of superconductivity and charge-density waves in a two-dimensional Holstein model at half-filling

S. Sykora·A. Hübsch·K. W. Becker

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Abstract

In one dimension the coupling of electrons to phonons leads to a transition from a metallic to a Peierls distorted insulated state if the coupling exceeds a critical value. On the other hand, in two dimensions the electron-phonon interaction may also lead to the formation of Cooper pairs. This competition of superconductivity and charge order (in conjunction with a lattice distortion) is studied in this letter by means of the projector-based renormalization method (PRM). Increasing the electron-phonon interaction, we find a crossover behavior between a purely superconducting state and a charge-density wave where a well-defined parameter range of coexistence of superconductivity and lattice distortion exists.

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S. Sykora, A. Hübsch, K. W. Becker. 2008-08-29. Coexistence of superconductivity and charge-density waves in a two-dimensional Holstein model at half-filling. https://doi.org/10.1209/0295-5075/85/57003

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