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arXiv · 1004.4650

Ferromagnetism of cold fermions loaded into a decorated square lattice

Kazuto Noda·Akihisa Koga·Norio Kawakami·Thomas Pruschke
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Abstract

We investigate two-component ultracold fermions loaded into a decorated square lattice, which are described by the Hubbard model with repulsive interactions and nearest neighbor hoppings. By combining the real-space dynamical mean-field theory with the numerical renormalization group method, we discuss how a ferromagnetically ordered ground state in the weak coupling regime, which originates from the existence of a dispersionless band, is adiabatically connected to a Heisenberg ferrimagnetic state in the strong coupling limit. The effects of level splitting and hopping imbalance are also addressed.

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Kazuto Noda, Akihisa Koga, Norio Kawakami, Thomas Pruschke. 2010-04-26. Ferromagnetism of cold fermions loaded into a decorated square lattice. https://doi.org/10.1103/physreva.80.063622

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