6533b7d2fe1ef96bd125eb2a
RESEARCH PRODUCT
Large Dzyaloshinskii-Moriya interaction and room-temperature nanoscale skyrmions in CoFeB/MgO heterostructures
Xinran WangKaihua CaoDanrong XiongSai LiJun-young KimKyujoon LeeShouzhong PengXueying ZhangRunze ChenWeisheng ZhaoMathias KläuiHongchao ZhangHongxin YangHouyi Chengsubject
Materials scienceCondensed matter physics530 PhysicsSkyrmionGeneral EngineeringGeneral Physics and AstronomyHeterojunctionGeneral Chemistry530 PhysikMetalBrillouin zoneTunnel magnetoresistanceGeneral Energyvisual_artvisual_art.visual_art_mediumGeneral Materials ScienceMagnetic force microscopeThin filmNanoscopic scaledescription
Summary Magnetic skyrmions in heavy metal (HM)/CoFeB/MgO structures are of particular interest for skyrmion-based magnetic tunnel junction (MTJ) devices because of their reliable generation, stability, and readout through purely electrical methods. To optimize the properties, such as stability, a strong Dzyaloshinskii-Moriya interaction (DMI) is required at room temperature. Here, using first-principles calculations, we demonstrate that huge DMI can be obtained in Ir/CoFe structures with an Fe-terminated configuration. Moreover, Brillouin light-scattering measurements show that indeed Ta/Ir/Co20Fe60B20/MgO thin films with perpendicular magnetic anisotropy exhibit a large DMI value (1.13 mJ/m2) when the thickness of the CoFeB layer is 1.1 nm, which can be attributed to the smooth and Fe-rich interface between Ir and CoFeB layers. Furthermore, we observe stable sub-100 nm magnetic skyrmions at room temperature in the Ir/CoFeB/MgO systems by magnetic force microscope. This work paves the way for promoting the application of skyrmions in CoFeB/MgO-based perpendicular anisotropy MTJ structures.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2021-11-01 |