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Possible high $T_c$ superconductivity mediated by antiferromagnetic spin fluctuations in systems with Fermi surface pockets

Kazuhiko Kuroki·Ryotaro Arita
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Abstract

We propose that if there are two small pocket-like Fermi surfaces, and the spin susceptibility is pronounced around a wave vector {\bf Q} that bridges the two pockets, the spin-singlet superconductivity mediated by spin fluctuations may have a high transition temperature. Using the fluctuation exchange approximation, this idea is confirmed for the Hubbard on a lattice with alternating hopping integrals, for which $T_c$ is estimated to be almost an order of magnitude larger than those for systems with a large connected Fermi surface.

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Kazuhiko Kuroki, Ryotaro Arita. 2001-01-29. Possible high $T_c$ superconductivity mediated by antiferromagnetic spin fluctuations in systems with Fermi surface pockets. https://doi.org/10.1103/physrevb.64.024501

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