1. Ferrimagnetism of ultracold fermions in a multi-band Hubbard system
- Author
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Lebrat, Martin, Kale, Anant, Kendrick, Lev Haldar, Xu, Muqing, Gang, Youqi, Nikolaenko, Alexander, Sachdev, Subir, and Greiner, Markus
- Subjects
Condensed Matter - Quantum Gases ,Condensed Matter - Strongly Correlated Electrons ,Quantum Physics - Abstract
Strongly correlated materials feature multiple electronic orbitals which are crucial to accurately understand their many-body properties, from cuprate materials to twisted bilayer graphene. In such multi-band models, quantum interference can lead to dispersionless bands whose large degeneracy gives rise to itinerant magnetism even with weak interactions. Here, we report on signatures of a ferrimagnetic state realized in a Lieb lattice at half-filling, characterized by antialigned magnetic moments with antiferromagnetic correlations, concomitant with a finite spin polarization. We demonstrate its robustness when increasing repulsive interactions from the non-interacting to the Heisenberg regime, and study its emergence when continuously tuning the lattice unit cell from a square to a Lieb geometry. Our work paves the way towards exploring exotic phases in related multi-orbital models such as quantum spin liquids in kagome lattices and heavy fermion behavior in Kondo models., Comment: 7+8 pages, 4+11 figures
- Published
- 2024