Cheng Haixia, Sun Xu, Zhou Jun, Wang Shijie, Su Hang, Ji Wei
Material Digital R&D Center, China Iron & Steel Research Institute Group, Beijing 100081, China.
Division of Functional Materials, Central Iron and Steel Research Institute, Beijing 100081, China.
ACS Appl Mater Interfaces. 2024 Sep 4;16(35):46570-46577. doi: 10.1021/acsami.4c07562. Epub 2024 Aug 21.
Ferroelectric Rashba semiconductors (FRS) are highly demanded for their potential capability for nonvolatile electric control of electron spins. An ideal FRS is characterized by a combination of room temperature ferroelectricity and a strong Rashba effect, which has, however, been rarely reported. Herein, we designed a room-temperature FRS by vertically stacking a Sb monolayer on a room-temperature ferroelectric InSe monolayer. Our first-principles calculations reveal that the Sb/InSe heterostructure exhibits a clean Rashba splitting band near the Fermi level and a strong Rashba effect coupled to the ferroelectric order. Switching the electric polarization direction enhances the Rashba effect, and the flipping is feasible with a low energy barrier of 22 meV. This Rashba-ferroelectricity coupling effect is robust against changes of the heterostructure interfacial distance and external electric fields. Such a nonvolatile electrically tunable Rashba effect at room temperature enables potential applications in next-generation data storage and logic devices operated under small electrical currents.
铁电 Rashba 半导体（FRS）因其对电子自旋进行非易失性电控制的潜在能力而备受关注。理想的 FRS 具有室温铁电性和强 Rashba 效应的组合，但这种情况很少被报道。在此，我们通过在室温铁电 InSe 单层上垂直堆叠 Sb 单层来设计一种室温 FRS。我们的第一性原理计算表明，Sb/InSe 异质结构在费米能级附近呈现出清晰的 Rashba 分裂带，并且存在与铁电序耦合的强 Rashba 效应。切换电极化方向会增强 Rashba 效应，且翻转具有 22 meV 的低能垒，这是可行的。这种 Rashba - 铁电耦合效应对于异质结构界面距离和外部电场的变化具有鲁棒性。这种室温下非易失性电可调的 Rashba 效应使得其在下一代小电流运行的数据存储和逻辑器件中具有潜在应用。
