Kinetic magnetism in the crossover between the square and triangular lattice Fermi-Hubbard models
Fuente:
arXiv
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866909963711938560 |
|---|---|
| author | Pereira, Darren Mueller, Erich J. |
| author_facet | Pereira, Darren Mueller, Erich J. |
| contents | We calculate the spin correlations that result from the motion of a single dopant in the hard-core Fermi-Hubbard model, as the geometry evolves from a square to a triangular lattice. In particular, we consider the square lattice with an additional hopping along one diagonal, whose strength is continuously varied. We use a high-temperature expansion which expresses the partition function as a sum over closed paths taken by the dopant. We sample thousands of diagrams in the space of closed paths using the quantum Monte Carlo approach of Raghavan and Elser [1,2], which is free of finite-size effects and allows us to simulate temperatures as low as $T \sim 0.3|t|$, even in cases where there is a sign problem. For the case of a hole dopant, we find a crossover from kinetic ferromagnetism to kinetic antiferromagnetism as the geometry is tuned from square to triangular, which can be observed in current quantum gas microscopes. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2506_15669 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Kinetic magnetism in the crossover between the square and triangular lattice Fermi-Hubbard models Pereira, Darren Mueller, Erich J. Strongly Correlated Electrons Quantum Gases Statistical Mechanics Quantum Physics We calculate the spin correlations that result from the motion of a single dopant in the hard-core Fermi-Hubbard model, as the geometry evolves from a square to a triangular lattice. In particular, we consider the square lattice with an additional hopping along one diagonal, whose strength is continuously varied. We use a high-temperature expansion which expresses the partition function as a sum over closed paths taken by the dopant. We sample thousands of diagrams in the space of closed paths using the quantum Monte Carlo approach of Raghavan and Elser [1,2], which is free of finite-size effects and allows us to simulate temperatures as low as $T \sim 0.3|t|$, even in cases where there is a sign problem. For the case of a hole dopant, we find a crossover from kinetic ferromagnetism to kinetic antiferromagnetism as the geometry is tuned from square to triangular, which can be observed in current quantum gas microscopes. |
| title | Kinetic magnetism in the crossover between the square and triangular lattice Fermi-Hubbard models |
| topic | Strongly Correlated Electrons Quantum Gases Statistical Mechanics Quantum Physics |
| url | https://arxiv.org/abs/2506.15669 |