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arXiv · 2409.08848

Magnetic phase diagram of the three-dimensional doped Hubbard model

Liam Rampon·Fedor Šimkovic IV·Michel Ferrero
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Abstract

We establish the phase diagram of the Hubbard model on a cubic lattice for a wide range of temperatures, dopings and interaction strengths, considering both commensurate and incommensurate magnetic orders. We use the dynamical mean-field theory together with an efficient method to compute the free energy which enable the determination of the correct ordering vectors. Besides an antiferromagnetic state close to half-filling, we identify a number of different magnetic spiral phases with ordering vectors $(q,\pi,\pi)$, $(q,q,\pi)$ and $(q,q,q)$ as well as a region with close competition between them, hinting at spatial phase separation or at the onset of a stripe phase. Additionally, we extensively study several thermodynamic properties with direct relevance to cold-atom experiments: the entropy, energy and double-occupancy.

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Liam Rampon, Fedor Šimkovic IV, Michel Ferrero. 2024-09-13. Magnetic phase diagram of the three-dimensional doped Hubbard model. https://doi.org/10.1103/physrevlett.134.066502

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