National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing, People's Republic of China.
Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, People's Republic of China.
Nature. 2022 Mar;603(7899):63-67. doi: 10.1038/s41586-021-04338-w. Epub 2022 Mar 2.
Topological domains in ferroelectrics have received much attention recently owing to their novel functionalities and potential applications in electronic devices. So far, however, such topological polar structures have been observed only in superlattices grown on oxide substrates, which limits their applications in silicon-based electronics. Here we report the realization of room-temperature skyrmion-like polar nanodomains in lead titanate/strontium titanate bilayers transferred onto silicon. Moreover, an external electric field can reversibly switch these nanodomains into the other type of polar texture, which substantially modifies their resistive behaviours. The polar-configuration-modulated resistance is ascribed to the distinct band bending and charge carrier distribution in the core of the two types of polar texture. The integration of high-density (more than 200 gigabits per square inch) switchable skyrmion-like polar nanodomains on silicon may enable non-volatile memory applications using topological polar structures in oxides.
拓扑畴在铁电体中受到了广泛关注，因为它们具有新颖的功能和在电子设备中的潜在应用。然而，到目前为止，这种拓扑极性结构仅在氧化物衬底上生长的超晶格中观察到，这限制了它们在基于硅的电子学中的应用。在这里，我们报告了在转移到硅上的钛酸铅/钛酸锶双层薄膜中实现了室温类斯格明子的极性纳米畴。此外，外部电场可以将这些纳米畴可逆地切换成另一种类型的极性织构，这大大改变了它们的电阻行为。这种由极性构型调制的电阻归因于两种类型的极性织构核心中不同的能带弯曲和电荷载流子分布。在硅上集成高密度（每平方英寸超过 200 吉比特）可切换类斯格明子的极性纳米畴，可能会使基于氧化物的拓扑极性结构在非易失性存储器应用中成为可能。
