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On-Site Repulsion as the Source of Pairing in Carbon Nanotubes and Intercalated Graphite

Enrico Perfetto·Gianluca Stefanucci·Michele Cini
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Abstract

We show that different non-conventional superconductors have one fundamental feature in common: pair eigenstates of the Hamiltonian are repulsion-free, the W=0 pairs. In extended Hubbard models, pairing can occur for resonable parameter values. For $(N,N)$ nanotubes the binding energy of the pair depends strongly on the filling and decreases towards a reduced but nonzero value for the graphite sheet $N \to \infty$.

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Enrico Perfetto, Gianluca Stefanucci, Michele Cini. 2002-12-05. On-Site Repulsion as the Source of Pairing in Carbon Nanotubes and Intercalated Graphite. https://doi.org/10.1140/epjb%2Fe2002-00367-6

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