双粒子拓扑Thouless自旋泵

最近，加拿大麦克马斯特大学J. Mumford研究团队探究了双粒子拓扑Thouless自旋泵。相关成果已于2023年3月6日在国际学术期刊《物理评论A》上发表。

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该研究团队展示了两个粒子通过自旋交换相互作用表现出在一维单粒子晶格模型中发现的拓扑特征。通过将晶格的所有空间自由度吸收到两个粒子的自旋自由度中，实现了这一目标。同时，将自旋系统与Su-Schrieffer-Heeger模型进行比较，研究团队证明了拓扑保护边缘自旋态的存在，并建立了体积-边缘对应关系。

他们通过引入一个手性对称性破缺项来修改自旋系统，使其类似于Rice-Mele模型，因此在周期性和绝热驱动时可以作为其中一个粒子的Thouless自旋泵。通过将自旋态作为一个合成空间维度，研究团队表明两个粒子足以模拟凝聚态物理中众所周知的拓扑性质。

附：英文原文

Title: Two-particle topological Thouless spin pump

Author: J. Mumford

Issue&Volume: 2023/03/06

Abstract: We show that two particles interacting via spin exchange exhibit topological features found in one-dimensional single-particle lattice models. This is accomplished by absorbing all of the spatial degrees of freedom of the lattice into the spin degrees of freedom of the two particles. Comparing the spin system with the Su-Schrieffer-Heeger model, we show the existence of topologically protected edge spin states and establish the bulk-edge correspondence. Modifying the spin system with a chiral symmetry-breaking term results in it resembling the Rice-Mele model and can therefore act as a Thouless spin pump of one of the particles when periodically and adiabatically driven. By using the spin states as a synthetic spatial dimension, we show two particles are enough to simulate well-known topological properties in condensed matter physics.

DOI: 10.1103/PhysRevA.107.033302

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.107.033302

来源：科学网小柯机器人