近日，美国华盛顿大学的Xiaodong Xu&Jiun-Haw Chu及其研究团队取得一项新进展。经过不懈努力，他们对关联反铁磁体中残余三态波茨向列的应变调谐进行研究。相关研究成果已于2024年10月10日在国际知名学术期刊《自然—物理学》上发表。
该研究团队展示了在FePSe3中，作为之字形反铁磁性的残余序，通过应变控制三态波茨向列性的方法。光学线性二向色性测量揭示了向列态，并证明了单轴应变下向列指向的旋转。研究表明，向列相变的性质也可以通过应变来控制，从而实现波茨向列相变与伊辛向列翻转相变之间的平滑交叉过渡。弹热测量显示了两个耦合相变的特征，表明残余向列相变与反铁磁相变是分离的。这确立了FePSe3作为探索三态波茨残余向列性的一个系统。
据悉，电子向列性是一种物质状态，其中旋转对称性自发破缺，而平移对称性得以保持。在强关联材料中，向列性通常源于多分量初级序（如自旋或电荷密度波）的波动，并被称为残余向列性。一个广泛研究的例子是伊辛向列性，它作为四方铁基磷族超导体中共线反铁磁性的残余序而出现。由于晶体中的向列指向受底层晶体对称性的限制，最近发现的具有三重旋转对称性的量子材料为研究具有三态波茨特性的向列序提供了新的平台。
附：英文原文
Title: Strain tuning of vestigial three-state Potts nematicity in a correlated antiferromagnet
Author: Hwangbo, Kyle, Rosenberg, Elliott, Cenker, John, Jiang, Qianni, Wen, Haidan, Xiao, Di, Chu, Jiun-Haw, Xu, Xiaodong
Issue&Volume: 2024-10-10
Abstract: Electronic nematicity is a state of matter in which rotational symmetry is spontaneously broken and translational symmetry is preserved. In strongly correlated materials, nematicity often emerges from fluctuations of a multicomponent primary order, such as spin or charge density waves, and is termed vestigial nematicity. One widely studied example is Ising nematicity, which arises as a vestigial order of collinear antiferromagnetism in the tetragonal iron pnictide superconductors. Because nematic directors in crystals are restricted by the underlying crystal symmetry, recently identified quantum materials with three-fold rotational symmetry offer a new platform to investigate nematic order with three-state Potts character. Here we demonstrate strain control of three-state Potts nematicity as a vestigial order of zigzag antiferromagnetism in FePSe3. Optical linear dichroism measurements reveal the nematic state and demonstrate the rotation of the nematic director by uniaxial strain. We show that the nature of the nematic phase transition can also be controlled by strain, inducing a smooth crossover transition between a Potts nematic transition and an Ising nematic flop transition. Elastocaloric measurements demonstrate the signatures of two coupled phase transitions, indicating that the vestigial nematic transition is separated from the antiferromagnetic transition. This establishes FePSe3 as a system to explore three-state Potts vestigial nematicity.
DOI: 10.1038/s41567-024-02653-3
Source: https://www.nature.com/articles/s41567-024-02653-3