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arXiv · 2008.12770

Tunnel magnetoresistance in scandium nitride magnetic tunnel junctions using first principles

Suyogya Karki·Vivian Rogers·Priyamvada Jadaun·Daniel S. Marshall·Jean Anne C. Incorvia
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Abstract

The magnetic tunnel junction is a cornerstone of spintronic devices and circuits, providing the main way to convert between magnetic and electrical information. In state-of-the-art magnetic tunnel junctions, magnesium oxide is used as the tunnel barrier between magnetic electrodes, providing a uniquely large tunnel magnetoresistance at room temperature. However, the wide bandgap and band alignment of magnesium oxide-iron systems increases the resistance-area product and causes challenges of device-to-device variability and tunnel barrier degradation under high current. Here, we study using first principles narrower-bandgap scandium nitride tunneling properties and transport in magnetic tunnel junctions in comparison to magnesium oxide. These simulations demonstrate a high tunnel magnetoresistance in Fe/ScN/Fe MTJs via {\Delta}_1 and {\Delta}_2' symmetry filtering with low wavefunction decay rates, allowing a low resistance-area product. The results show that scandium nitride could be a new tunnel barrier material for magnetic tunnel junction devices to overcome variability and current-injection challenges.

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Suyogya Karki, Vivian Rogers, Priyamvada Jadaun, Daniel S. Marshall, Jean Anne C. Incorvia. 2020-08-28. Tunnel magnetoresistance in scandium nitride magnetic tunnel junctions using first principles. https://arxiv.org/abs/2008.12770

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