Ferromagnetism and skyrmions in the Hofstadter–Fermi–Hubbard model
Ferromagnetism and skyrmions in the Hofstadter–Fermi–Hubbard model
复制标题
霍夫施塔特-费米-哈伯德模型中的铁磁性和斯格明子
DOI：
10.1088/1367-2630/acb963
复制
发表时间：
2023
影响因子：
3.3
通讯作者：
Grusdt, F
中科院分区：
文献类型：
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作者：
Palm, F A;Kurttutan, M;Bohrdt, A;Schollwöck, U;Grusdt, F
强相互作用的费米子系统拥有各种有趣的具有奇异激发的量子多体态。例如，强相互作用和泡利不相容原理的相互作用可以导致斯通铁磁性，但当加入动力学项时，这种状态的命运仍然不清楚。虽然在许多晶格模型中，费米子的色散会导致铁磁的离域和失稳，但平坦的能带可以恢复强烈的相互作用效应和铁磁关联。为了揭示这种相互作用，我们建议使用超冷原子来研究Hofstadter-Fermi-Hubbard模型。通过进行大规模的密度矩阵重整化群模拟，我们证明了该模型在磁填充因子ν=1时表现为量子霍尔(QH)铁磁体的晶格模拟。我们揭示了ν≈1周围低能自旋单线态的本质，并发现它们承载着类似于Skyrmion的自旋-自旋关联的准粒子和准空穴。最后，我们预测了平带铁磁性在大场中的击穿。我们的工作为晶格QH铁磁性的实验研究铺平了道路，包括研究相互作用的Skyrmions的多体状态和探索与高密度的关系.
Strongly interacting fermionic systems host a variety of interesting quantum many-body states with exotic excitations. For instance, the interplay of strong interactions and the Pauli exclusion principle can lead to Stoner ferromagnetism, but the fate of this state remains unclear when kinetic terms are added. While in many lattice models the fermions' dispersion results in delocalization and destabilization of the ferromagnet, flat bands can restore strong interaction effects and ferromagnetic correlations. To reveal this interplay, here we propose to study the Hofstadter–Fermi–Hubbard model using ultracold atoms. We demonstrate, by performing large-scale density-matrix renormalization group simulations, that this model exhibits a lattice analog of the quantum Hall (QH) ferromagnet at magnetic filling factor ν= 1. We reveal the nature of the low energy spin-singlet states around ν≈ 1 and find that they host quasi-particles and quasi-holes exhibiting spin-spin correlations reminiscent of skyrmions. Finally, we predict the breakdown of flat-band ferromagnetism at large fields. Our work paves the way towards experimental studies of lattice QH ferromagnetism, including prospects to study many-body states of interacting skyrmions and explore the relation to high-
DOI：
--
发表时间：
2006
期刊：
--
影响因子：
--
作者：
Iroon Polytechniou-
通讯作者：
Iroon Polytechniou-