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arXiv · 2209.10673

Flat bands and unconventional superconductivity in a simple model of metal-organic frameworks

M. F. Ohlrich·E. M. Makaresz·H. L. Nourse·B. J. Powell
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Abstract

The superconducting metal-organic framework Cu-BHT forms a kagome lattice with metals at the vertices and ligands along the bonds. This bipartite motif is common in reticular materials. We show that a tight-binding model on this lattice yields partially occupied interference-induced flat bands at half-filling with large gaps between them and all other bands. Long-range hopping induces curvature in the bands but leaves them flatter and more isolated than those in twisted bilayer graphene. The slave boson theory of the t-J model on this lattice shows highly unconventional superconductivity including an f -wave singlet phase. Thus, framework materials provide an ideal lattice-driven approach to strongly correlated phenomena in flat bands at high electronic densities.

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M. F. Ohlrich, E. M. Makaresz, H. L. Nourse, B. J. Powell. 2022-09-21. Flat bands and unconventional superconductivity in a simple model of metal-organic frameworks. https://arxiv.org/abs/2209.10673

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