AI 中文总结
本文研究了具有铁四极序的反铁磁拓扑绝缘体候选材料DyPtBi，发现其磁畴壁可通过单轴应力和磁场调控，揭示了其拓扑电子态与多极自由度的纠缠，为拓扑性质原位调控提供了新途径。
AI 中文摘要
反铁磁拓扑绝缘体提供了一个丰富的平台，其中对称性破缺的磁序与拓扑电子态相互交织。特别地，磁畴壁受到广泛关注，因为它们可像普通磁体一样通过外场轻松调控，且还拥有与体相和样品表面不同的非平庸电子态。本文报道了一种新型反铁磁拓扑绝缘体候选材料DyPtBi，其具有可通过单轴应力和磁场调控的导电磁畴壁。我们发现，在磁相变和结构相变发生时，电阻率会急剧上升；与此同时，横向超声模式出现了6%的显著软化，表明Dy的4f铁四极序在该相变中起到至关重要的作用。此外，我们通过中子实验揭示，施加压缩单轴应力可使磁畴态排列，在消除导电磁畴壁的同时，导致电阻率大幅提升14%。这些发现表明，DyPtBi展现出与多极自由度纠缠的拓扑电子态，为拓扑性质的原位调控提供了一条有前景的途径。
英文摘要
Antiferromagnetic topological insulators provide a fertile platform where symmetry-breaking magnetic order is intertwined with topological electronic states. In particular, magnetic domain walls have attracted much attention, as they can be easily controlled by external fields as in general magnets, and moreover, host nontrivial electronic states distinct from those in bulks and sample surfaces. Here, we report a new antiferromagnetic topological insulator candidate DyPtBi, which hosts conductive magnetic domain walls controllable by uniaxial stress and magnetic field. We find that the resistivity exhibits abrupt increase upon the magnetic and structural phase transition. Concomitantly, the transverse ultrasonic mode shows remarkable softening of 6 %, indicating that the Dy 4f ferroquadrupolar order plays a vital role in the phase transition. Furthermore, we reveal by neutron experiments that applying compressive uniaxial stress aligns the magnetic domain state, leading to the strong resistivity enhancement of 14 % while eliminating the conductive magnetic domain walls. These findings demonstrate that DyPtBi exhibits topological electronic states entangled with multipolar degrees of freedom, providing a promising route for in situ control of topological properties.
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