Negative tunneling magnetoresistance of Fe/MgO/NiO/Fe magnetic tunnel junction: Role of spin mixing and interface state

发布时间： 2018-11-13 点击次数：

• 所属单位：理学院
• 发表刊物：APPLIED PHYSICS LETTERS
• 关键字：AB-INITIO SPINTRONICS CONDUCTANCE FUTURE BIAS
• 摘要：Motivated by a recent tunneling magnetoresistance (TMR) measurement in which the negative TMR is observed in MgO/NiO-based magnetic tunnel junctions (MTJs), we have performed systematic calculations of transmission, current, and TMR of Fe/MgO/NiO/Fe MTJ with different thicknesses of NiO and MgO layers based on noncollinear density functional theory and non-equilibrium Green's function theory. The calculations show that, as the thickness of NiO and MgO layers is small, the negative TMR can be obtained which is attributed to the spin mixing effect and interface state. However, in the thick MTJ, the spin-flipping scattering becomes weaker, and thus, the MTJs recover positive TMR. Based on our theoretical results, we believe that the interface state at Fe/NiO interface and the spin mixing effect induced by noncollinear interfacial magnetization will play important role in determining transmission and current of Fe/MgO/NiO/Fe MTJ. The results reported here will be important in understanding the electron tunneling in MTJ with the barrier made by transition metal oxide. Published by AIP Publishing.
• ISSN号：0003-6951
• 是否译文：否
• 合写作者：颜晓红,Guo, Y. D.,肖杨
• 通讯作者：颜晓红,张影
• 发表时间：2017-08-14