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arXiv · 1901.10563

Effective pairing interaction in a system with an incipient band

Thomas A. Maier·Vivek Mishra·Douglas J. Scalapino
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Abstract

The nature and mechanism of superconductivity in the extremely electron-doped FeSe based superconductors continues to be a matter of debate. In these systems, the hole-like band has moved below the Fermi energy, and various spin-fluctuation theories involving pairing between states near the electron Fermi surface and states of this incipient band have been proposed. Here, using a dynamic cluster quantum Monte Carlo calculation for a bilayer Hubbard model we show that the pairing in these systems can be understood in terms of an effective retarded attractive interaction between electrons near the electron Fermi surface.

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Thomas A. Maier, Vivek Mishra, Douglas J. Scalapino. 2019-01-29. Effective pairing interaction in a system with an incipient band. https://doi.org/10.1103/physrevb.99.140504

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