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arXiv · 2208.09947

Enhanced magnetoresistance in perpendicular magnetic tunneling junctions with MgAl2O4 barrier

Pravin Khanal·Bowei Zhou·Magda Andrade·Christopher Mastrangelo·Ali Habiboglu·Arthur Enriquez·Daulton Fox·Kennedy Warrilow·Wei-Gang Wang
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Abstract

Perpendicular magnetic tunnel junction with MgAl2O4 barrier is investigated. It is found that reactive RF sputtering with O2 is essential to obtain strong perpendicular magnetic anisotropy and large tunneling magnetoresistance in MgAl2O4-based junctions. An interfacial perpendicular magnetic anisotropy energy density of 2.25 mJ/m2 is obtained for the samples annealed at 400C. An enhanced magnetoresistance of 60% has also been achieved. The Vhalf, bias voltage at which tunneling magnetoresistance drops to half of the zero-bias value, is found to be about 1V, which is substantially higher than that of MgO-based junctions.

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Pravin Khanal, Bowei Zhou, Magda Andrade, Christopher Mastrangelo, Ali Habiboglu, Arthur Enriquez, Daulton Fox, Kennedy Warrilow, Wei-Gang Wang. 2022-08-21. Enhanced magnetoresistance in perpendicular magnetic tunneling junctions with MgAl2O4 barrier. https://doi.org/10.1016/j.jmmm.2022.169914

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