Effect of oxide barrier height in spin dependent tunneling in MTJ of FeO-MgO multilayer structure

27th IUPAP Conference on Computational Physics

物理学;计算机科学

Bhattacharjee, M.^1 ; Nemade, H.^1,3 ; Bandyopadhyay, D.^1,2

Centre for Nanotechnology, Indian Institute of Technology, Guwahati, India^1

Department of Chemical Engineering, Indian Institute of Technology, Guwahati, India^2

Department of Electronics and Electrical Engineering, Indian Institute of Technology, Guwahati, India^3

关键词: Atomistic modeling;    Barrier heights;    Magnetic tunnel junction;    Multilayer structures;    Non-equilibrium Green's function;    Oxide layer thickness;    Spin dependent tunneling;    Structural models;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/759/1/012051/pdf
DOI  :  10.1088/1742-6596/759/1/012051

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

We study the spin dependent tunneling current properties through oxide multilayers in a magnetic tunnel junction (MTJ). For this purpose, nonequilibrium Green's function approach along-with the density-functional theory have been applied. We employed three structural models of FeO-MgO-FeO multi-layer with three different width of FeO and MgO layer. An atomistic model is considered to describe the effect of oxide multilayers of different heights. Spin dependent study for tunneling reveals that the parallel spin shows higher tunneling current whereas anti-parallel spin conducts very less. Further, the lowest tunneling current is obtained for the case where the FeO and MgO each has 3 atomic layers of height whereas the tunneling current is highest in 4 atomic layers of FeO/1 atomic layers of MgO/4 atomic layers of MgO multilayer structure. Importantly, when the MgO or FeO layers are increased or decreased from this level, the tunneling current decreases significantly. The study reveals that the layer height in the tunneling domain can be important factor for tuning and adjusting tunneling current in the nanoscale regime of oxide layer thickness.