Ferromagnetism in d-Dimensional SU(n) Hubbard Models with Nearly Flat Bands

  title={Ferromagnetism in d-Dimensional SU(n) Hubbard Models with Nearly Flat Bands},
  author={Kensuke Tamura and Hosho Katsura},
  journal={Journal of Statistical Physics},
We present rigorous results for the SU( n ) Fermi–Hubbard models with finite-range hopping in d ( $$\ge 2$$ ≥ 2 ) dimensions. The models are defined on a class of decorated lattices. We first study the models with flat bands at the bottom of the single-particle spectrum and prove that the ground states exhibit SU( n ) ferromagnetism when the number of particles is equal to the number of unit cells. We then perturb the models by adding particular hopping terms and make the bottom bands… 

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    Graduate Texts in Physics
  • 2020

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