Coupling a Mobile Hole to an Antiferromagnetic Spin Background: Transient Dynamics of a Magnetic Polaron
Coupling a Mobile Hole to an Antiferromagnetic Spin Background: Transient Dynamics of a Magnetic Polaron
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DOI：
10.1103/physrevx.11.021022
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发表时间：
2021-04-27
影响因子：
12.5
通讯作者：
Greiner, Markus
中科院分区：
文献类型：
--
作者：
Ji, Geoffrey;Xu, Muqing;Greiner, Markus
理解电荷和自旋之间的相互作用及其对输运的影响是量子多体系统中普遍存在的挑战。在费米-哈伯德模型中，这种相互作用被认为会产生磁极化子，其动力学可以解释量子材料的涌现特性，如高温超导性。在这项工作中，我们使用冷原子量子模拟器直接观察单个磁极化子的形成动力学和随后的扩展。测量密度和自旋分辨的演变，一个单一的孔在一个二维哈伯德绝缘体与短程反铁磁相关揭示快速初始离域和敷料的自旋背景，表明极化子的形成。在较长的时间，我们发现动力学减慢的自旋交换时间，它们是兼容的极化模型与强密度和自旋耦合。我们的工作使费米-哈伯德模型中的非平衡涌现现象的研究，一次一个掺杂剂。
Understanding the interplay between charge and spin and its effects on transport is a ubiquitous challenge in quantum many-body systems. In the Fermi-Hubbard model, this interplay is thought to give rise to magnetic polarons, whose dynamics may explain emergent properties of quantum materials such as high-temperature superconductivity. In this work, we use a cold-atom quantum simulator to directly observe the formation dynamics and subsequent spreading of individual magnetic polarons. Measuring the density- and spin-resolved evolution of a single hole in a 2D Hubbard insulator with short-range antiferromagnetic correlations reveals fast initial delocalization and a dressing of the spin background, indicating polaron formation. At long times, we find that dynamics are slowed down by the spin exchange time, and they are compatible with a polaronic model with strong density and spin coupling. Our work enables the study of out-of-equilibrium emergent phenomena in the Fermi-Hubbard model, one dopant at a time.