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arXiv · 1805.08603

Search for alternative magnetic tunnel junctions based on all-Heusler stacks

Worasak Rotjanapittayakul·Jariyanee Prasongkit·Ivan Rungger·Stefano Sanvito·Wanchai Pijitrojana·Thomas Archer
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Abstract

By imposing the constraints of structural compatibility, stability and a large tunneling magneto-resistance, we have identified the Fe$_3$Al/BiF$_3$/Fe$_3$Al stack as a possible alternative to the well-established FeCoB/MgO/FeCoB in the search for a novel materials platform for high-performance magnetic tunnel junctions. Various geometries of the Fe$_3$Al/BiF$_3$/Fe$_3$Al structure have been analyzed, demonstrating that a barrier of less than 2~nm yields a tunneling magneto-resistance in excess of 25,000~\% at low bias, without the need for the electrodes to be half-metallic. Importantly, the presence of a significant spin gap in Fe$_3$Al for states with $Δ_1$ symmetry along the stack direction makes the TMR very resilient to high voltages.

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Worasak Rotjanapittayakul, Jariyanee Prasongkit, Ivan Rungger, Stefano Sanvito, Wanchai Pijitrojana, Thomas Archer. 2018-05-18. Search for alternative magnetic tunnel junctions based on all-Heusler stacks. https://doi.org/10.1103/physrevb.98.054425

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