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Superconductivity from Flat Dispersion Designed in Doped Mott Insulators

Masatoshi Imada·Masanori Kohno
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Abstract

Routes to enhance superconducting instability are explored for doped Mott insulators. With the help of insights for criticalities of metal-insulator transitions, geometrical design of lattice structure is proposed to control the instability. A guideline is to explicitly make flat band dispersions near the Fermi level without suppressing two-particle channels. In a one-dimensional model, numerical studies show that our prescription with finite-ranged hoppings realizes large enhancement of spin-gap and pairing dominant regions. We also propose several multi-band systems, where the pairing is driven by intersite Coulomb repulsion.

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Masatoshi Imada, Masanori Kohno. 1999-11-12. Superconductivity from Flat Dispersion Designed in Doped Mott Insulators. https://doi.org/10.1103/physrevlett.84.143

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