Das Purnendu, Leeb Valentin, Knolle Johannes, Knap Michael
<a href="https://ror.org/02kkvpp62">Technical University of Munich</a>, TUM School of Natural Sciences, Physics Department, 85748 Garching, Germany.
<a href="https://ror.org/04xrcta15">Munich Center for Quantum Science and Technology (MCQST)</a>, Schellingstr. 4, 80799 München, Germany.
Phys Rev Lett. 2024 Jun 28;132(26):263402. doi: 10.1103/PhysRevLett.132.263402.
Altermagnetism represents a type of collinear magnetism, that is in some aspects distinct from ferromagnetism and from conventional antiferromagnetism. In contrast to the latter, sublattices of opposite spin are related by spatial rotations and not only by translations and inversions. As a result, altermagnets have spin-split bands leading to unique experimental signatures. Here, we show theoretically how a d-wave altermagnetic phase can be realized with ultracold fermionic atoms in optical lattices. We propose an altermagnetic Hubbard model with anisotropic next-nearest neighbor hopping and obtain the Hartree-Fock phase diagram. The altermagnetic phase separates in a metallic and an insulating phase and is robust over a large parameter regime. We show that one of the defining characteristics of altermagnetism, the anisotropic spin transport, can be probed with trap-expansion experiments.
交替磁性是一种共线磁性，在某些方面不同于铁磁性和传统反铁磁性。与传统反铁磁性不同的是，具有相反自旋的子晶格通过空间旋转相关联，而不仅仅是通过平移和反演相关联。因此，交替磁体具有自旋分裂能带，从而导致独特的实验特征。在这里，我们从理论上展示了如何利用光学晶格中的超冷费米子原子实现d波交替磁相。我们提出了一个具有各向异性次近邻跳跃的交替磁性哈伯德模型，并得到了哈特里-福克相图。交替磁相分为金属相和绝缘相，并且在很大的参数范围内是稳定的。我们表明，交替磁性的一个决定性特征，即各向异性自旋输运，可以通过阱扩展实验来探测。
