Large Magnetoresistance in Scandium Nitride Magnetic Tunnel Junctions Using First Principles

Abstract

The state‐of‐the‐art magnetic tunnel junction, a cornerstone of spintronic devices and circuits, uses a magnesium oxide tunnel barrier that provides 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 creates variability and breakdown challenges. Here, the authors study using first principles narrower‐bandgap scandium nitride (ScN) transport properties in magnetoresistive junctions in comparison to magnesium oxide. The results show a high magnetoresistance in Fe/ScN/Fe via Δ1 and normalΔ2′ symmetry filtering with low wave function decay rates, suggesting scandium nitride could be a new barrier material for spintronic devices.

Ab initio Prediction of Mechanical, Electronic, Magnetic and Transport Properties of Bulk and Heterostructure of a Novel Fe-Cr based Full Heusler Chalcogenide

“…A high tolerance (10 −8 Ry) and a large k-mesh (100 points in both x and y directions) have been taken, which are required to capture the fine spikes in a transmission. 41 The scalar relativistic ultrasoft pseudopotentials(USPP) with the GGA exchange-correlation term have been used, as obtained from the PSLibrary 1.0.0. For further details of calculation of ballistic conductance see Ref.…”

Reversal of Band-Ordering Leads to High Hole Mobility in Strained p-type Scandium Nitride

“…Persistent photoconductivity in ScN has also been used to demonstrate optoelectronic artificial synaptic devices with memory and learning abilities . Theoretical calculations have also predicted that ScN would be an excellent barrier layer in magnetic tunnel junctions . Schottky diodes of ScN with elemental metals such as Au and Ag have been experimentally demonstrated recently …”

“…24 Theoretical calculations have also predicted that ScN would be an excellent barrier layer in magnetic tunnel junctions. 25 Schottky diodes of ScN with elemental metals such as Au and Ag have been experimentally demonstrated recently. 26 Traditionally, molecular beam epitaxy or magnetron sputterdeposited ScN thin films exhibit a high n-type carrier concentration in the (2−5) × 10 20 cm −3 range and electron mobility of 90−130 cm 2 /(V s) at room temperature.…”