单晶二维材料势垒层磁性隧道结温度效应的理论研究

Theoretical study on the effect of temperature in the magnetictunnel junctions with single crystal 2D-material barrier

基于传统光学衍射理论构建了适用于单晶势垒层磁性隧道结的理论模型.该理论模型将单晶势垒层视作周期性的衍射光栅,所以可以计入单晶势垒层对隧穿电子散射产生的相干性.利用此理论,研究了单晶二维材料势垒层磁性隧道结的温度效应.理论结果表明,由于隧穿电子波为势垒层散射而具有强相干性,所以隧穿电阻和TMR会随温度非单调变化.这解释了已有的实验结果,并阐明了其物理机制.此外,还研究了晶格畸变对单晶二维材料势垒层磁性隧道结温度特性的影响.这些研究结果为优化单晶二维材料势垒层磁性隧道结的温度特性奠定了坚实的理论基础.

This paper develops a tunneling theory based on the traditional optical diffraction theory for magnetic tunnel junctions with single crystal barrier.By the theory,the single crystal barrier is treated as a diffraction grating,so it can well account for the coherence of the tunneling electrons.Furthermore,the effect of temperature of the magnetic tunnel junctions with single crystal 2D-material barrier is studied.The theoretical result shows that,owing to the strong coherence of the tunneling electrons,the tunneling resistances and TMR will both vary with temperature non-monotonously.It can explain the experimental results in the previous literature,and clarify the physical mechanism.In addition,this paper has investigated the effects of lattice distortion on the temperature characteristics of the magnetic tunnel junctions with single crystal 2D-material barrier.The present work provides a solid theoretical foundation for optimizing the temperature characteristics of the magnetic tunnel junctions with single crystal 2D-material barrier.