Bakaul Saidur R, Prokhorenko Sergei, Zhang Qi, Nahas Yousra, Hu Yushi, Petford-Long Amanda, Bellaiche Laurent, Valanoor Nagarajan
Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA.
Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, 72701, USA.
Adv Mater. 2021 Nov;33(45):e2105432. doi: 10.1002/adma.202105432. Epub 2021 Sep 19.
Bubble-like domains, typically a precursor to the electrical skyrmions, arise in ultrathin complex oxide ferroelectric-dielectric-ferroelectric heterostructures epitaxially clamped with flat substrates. Here, it is reported that these specially ordered electric dipoles can also be retained in a freestanding state despite the presence of inhomogeneously distributed structural ripples. By probing local piezo and capacitive responses and using atomistic simulations, this study analyzes these ripples, sheds light on how the bubbles are stabilized in the modified electromechanical energy landscape, and discusses the difference in morphology between bubbles in freestanding and as-grown states. These results are anticipated to be the starting point of a new paradigm for the exploration of electric skyrmions with arbitrary boundaries and physically flexible topological orders in ferroelectric curvilinear space.
气泡状畴通常是电斯格明子的前驱体，出现在与平面衬底外延夹持的超薄复合氧化物铁电-介电-铁电异质结构中。在此，据报道，尽管存在分布不均匀的结构波纹，这些特殊排列的电偶极子仍能保持独立状态。通过探测局部压电和电容响应并使用原子模拟，本研究分析了这些波纹，揭示了气泡在修改后的机电能量景观中是如何稳定的，并讨论了独立状态和生长状态下气泡形态的差异。这些结果有望成为探索具有任意边界和铁电曲线空间中物理上灵活的拓扑序的电斯格明子新范式的起点。
