Adebanjo G D, Kornilovitch P E, Hague J P
School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, United Kingdom.
Department of Physics, Oregon State University, Corvallis, OR, 97331, United States of America.
J Phys Condens Matter. 2022 Jan 19;34(13). doi: 10.1088/1361-648X/ac484e.
The majority of fulleride superconductors with unusually high transition-temperature to kinetic-energy ratios have a face-centred-cubic (FCC) structure. We demonstrate that, within extended Hubbard models with strong Coulomb repulsion, paired fermions in FCC lattices have qualitatively different properties than pairs in other three-dimensional cubic lattices. Our results show that strongly bound, light, and small pairs can be generated in FCC lattices across a wide range of the parameter space. We estimate that such pairs can Bose condense at high temperatures even if the lattice constant is large (as in the fullerides).
