滑移铁电:理论、实验及潜在应用

Sliding ferroelectricity:theory,experiment,and potential applications

近年来,二维铁电受到了广泛关注,尤其是滑移铁电理论指出,大多数二维材料都可以通过层间堆叠产生垂直极化,并在电场下通过层间滑移翻转,这种独特的铁电机制已在多种范德瓦耳斯体系中得到了实验的广泛验证。文章综述了近期滑移铁电的理论和实验进展及其潜在应用:其独特的滑移机制使翻转势垒空前降低同时又保证了热稳定性,还可使信息写入高速低耗且抗疲劳;滑移铁电性与二维材料磁、光、超导、谷电子、拓扑性质、声子手性等丰富物性的耦合使它们可以被非易失性电控,相关的莫尔铁电、金属铁电、非线性霍尔效应等也极大丰富了铁电物理,为探索新奇物理现象和开发新型电子器件提供了广阔平台。目前已实现了滑移铁电单晶的大规模生长,基于滑移铁电的晶体管、神经形态忆阻器、光电子等器件的优越性能也得到验证,未经优化的翻转速度和抗疲劳性已能和目前成熟的铁电器件最优性能相比拟,未来前景可期。

In recent years,two-dimensional(2D)ferroelectrics have stimulated remarkable interest.Notably,the recently proposed concept of sliding ferroelectricity suggests that for most 2D materials,vertical polarization can be induced through interlayer stacking in their bilayers and multilayers,which are switchable upon interlayer sliding driven by a vertical electric field.Such sliding ferroelectricity has been extensively verified experimentally in a series of van der Waals systems.This paper will provide a concise review of the latest theoretical and experimental developments in sliding ferroelectrics,as well as their potential applications.The unique sliding mechanism significantly reduces the switching barrier while ensuring thermal stability,and also enables high-speed,low energy cost,and fatigue-resistant data writing,all of which have been confirmed experimentally.The coupling of sliding ferroelectricity with intrinsic physical properties of 2D monolayers(magnetism,excitonics,superconductivity,valleytronics,nontrivial topology,phonon chirality,etc.),allows for non-volatile electrical control of those properties.The related physics,like Moiréferroelectricity,metallic ferroelectricity,and the ferroelectric nonlinear anomalous Hall effect,have greatly enriched ferroelectric physics,providing a broad platform for exploring novel physical phenomena and developing new electronic devices.Currently,large-scale growth of sliding ferroelectric single crystals has been achieved experimentally.The superior performance of transistors,neuromorphic memristors,optoelectronics,and other devices based on sliding ferroelectrics has been verified.The unoptimized flipping speed and fatigue resistance are already comparable to the best performance of prevalent ferroelectric devices,indicating a promising future.