Electronic Correlation effects in superconducting picene from ab-initio calculations

Gianluca Giovannetti; Massimo Capone

doi:10.1103/physrevb.83.134508

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arXiv · 1011.3308

Electronic Correlation effects in superconducting picene from ab-initio calculations

Gianluca Giovannetti·Massimo Capone

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Abstract

We show, by means of ab-initio calculations, that electron-electron correlations play an important role in potassium-doped picene ($K_x$-picene), recently characterized as a superconductor with $T_c = 18K$. The inclusion of exchange interactions by means of hybrid functionals reproduces the correct gap for the undoped compound and predicts an antiferromagnetic state for $x=3$, where superconductivity has been observed. The latter finding is compatible with a sizable value of the correlation strength, in agreement with simple estimates. Our results highlight the similarity between potassium-doped picene and alkali-doped fulleride superconductors.

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Gianluca Giovannetti, Massimo Capone. 2011-04-09. Electronic Correlation effects in superconducting picene from ab-initio calculations. https://doi.org/10.1103/physrevb.83.134508

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