Sun Fei, Ren Jianhua, Li Hongfang, Zhang Yuan, Wu Yiwei, Liang Jianwei, Yang Hui, Liu Jianyi, Liu Linjie, Wu Mengjun, Zhang Xiaoyue, Zhu Wenpeng, Chen Weijin, Zhang Yi, Zheng Yue
Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, State Key Laboratory of Optoelectronic Materials and Technologies, Centre for Physical Mechanics and Biophysics, School of Physics, Sun Yat-sen University, Guangzhou, 510275, China.
School of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing, 400074, China.
Adv Mater. 2025 Jul;37(27):e2502674. doi: 10.1002/adma.202502674. Epub 2025 May 2.
Topological textures like vortices, labyrinths, and skyrmions formed in ferroic materials have attracted extensive interest during the past decade for their fundamental physics, intriguing topology, and technological prospects. So far, polar skyrmions remain scarce in ferroelectrics as they require a delicate balance between various dipolar interactions. Here, it is reported that PbTiO thin films in a metallic contact undergo a topological phase transition and hold a broad family of skyrmion-like textures including Q = ±1 skyrmions, multiple π-twist target skyrmions, and skyrmion bags, with independent controllability, analogous to those reported in magnetic systems. Weakly-interacted skyrmion arrays with a density over 300 Gbit/inch are successfully written, erased, and read out by local electrical and mechanical stimuli of a scanning probe. Interestingly, in contrast to the relatively short lifetime (<20 hours) of the normal skyrmions, the multiple π-twist target skyrmions and skyrmion bags show topology-enhanced stability with a lifetime of over two weeks. Experimental and theoretical analysis implies the heterostructures carry electric Dzyaloshinskii-Moriya interaction mediated by oxygen octahedral tiltings. The results demonstrate ferroelectric-metallic heterostructures as fertile playgrounds for topological states and emergent phenomena.
在过去十年中，铁性材料中形成的诸如涡旋、迷宫和斯格明子等拓扑纹理因其基础物理、引人入胜的拓扑结构和技术前景而备受关注。到目前为止，极性斯格明子在铁电体中仍然很少见，因为它们需要各种偶极相互作用之间的微妙平衡。在此，据报道，处于金属接触中的PbTiO薄膜会经历拓扑相变，并拥有包括Q = ±1斯格明子、多个π扭曲目标斯格明子和斯格明子袋在内的广泛的类斯格明子纹理家族，具有独立可控性，类似于在磁性系统中报道的那些。通过扫描探针的局部电和机械刺激，成功地写入、擦除并读出了密度超过300 Gbit/英寸的弱相互作用斯格明子阵列。有趣的是，与正常斯格明子相对较短的寿命（<20小时）相比，多个π扭曲目标斯格明子和斯格明子袋表现出拓扑增强的稳定性，寿命超过两周。实验和理论分析表明，异质结构携带由氧八面体倾斜介导的电Dzyaloshinskii-Moriya相互作用。结果表明，铁电-金属异质结构是拓扑态和涌现现象的丰富研究平台。
