Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al

We report on first-principles spin-polarised quantum transport calculations (from NEGF + DFT) in MgO-spaced magnetic tunnel junctions (MTJs) based on two different Mn-based Heusler ferrimagnetic metals, namely Mn3Al and Mn3Ga in their tetragonal DO22 phase. The former is a fully compensated half-met...

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Main Authors: M. Stamenova, P. Stamenov, N. Baadji
Format: Article
Language:English
Published: AIP Publishing LLC 2023-02-01
Series:AIP Advances
Online Access:http://dx.doi.org/10.1063/9.0000556
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author M. Stamenova
P. Stamenov
N. Baadji
author_facet M. Stamenova
P. Stamenov
N. Baadji
author_sort M. Stamenova
collection DOAJ
description We report on first-principles spin-polarised quantum transport calculations (from NEGF + DFT) in MgO-spaced magnetic tunnel junctions (MTJs) based on two different Mn-based Heusler ferrimagnetic metals, namely Mn3Al and Mn3Ga in their tetragonal DO22 phase. The former is a fully compensated half-metallic ferrimagnet, while the latter is a low-moment high-spin-polarisation ferrimagnet, both with a small lattice mismatch from MgO. In identical symmetric and asymmetric interface reconstructions across a 3-monolayer thick MgO barrier for both ferrimagets, the linear response (low-voltage) spin-transfer torque (STT) and tunneling magneto-resistance (TMR) effects are evaluated. A larger staggered in-plane STT is found in the Mn3Ga case, while the STT in Mn3Al vanishes quickly away from the interface (similarly to STT in ferromagnetic MTJs). The roles are reversed for the TMR, which is practically 100% in the half-metallic Mn3Al-based MTJs (using the conservative definition) as opposed to 60% in the Mn3Ga case. The weak dependence on the exact interface reconstruction would suggest Mn3Ga–Mn3Al solid solutions as a possible route towards optimal trade-off of STT and TMR in the low-bias, low-temperature transport regime.
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spelling doaj.art-79981b8f43a749f0a7191de9d6e0f6562023-03-10T17:26:19ZengAIP Publishing LLCAIP Advances2158-32262023-02-01132025016025016-610.1063/9.0000556Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3AlM. Stamenova0P. Stamenov1N. Baadji2School of Physics and CRANN, Trinity College Dublin, Dublin 2, IrelandSchool of Physics and CRANN, Trinity College Dublin, Dublin 2, IrelandLaboratoire de Physique des Matériaux et ses applications and Département de Physique, Faculté des Sciences, Université Mohamed Boudiaf, M’sila 28000, AlgerieWe report on first-principles spin-polarised quantum transport calculations (from NEGF + DFT) in MgO-spaced magnetic tunnel junctions (MTJs) based on two different Mn-based Heusler ferrimagnetic metals, namely Mn3Al and Mn3Ga in their tetragonal DO22 phase. The former is a fully compensated half-metallic ferrimagnet, while the latter is a low-moment high-spin-polarisation ferrimagnet, both with a small lattice mismatch from MgO. In identical symmetric and asymmetric interface reconstructions across a 3-monolayer thick MgO barrier for both ferrimagets, the linear response (low-voltage) spin-transfer torque (STT) and tunneling magneto-resistance (TMR) effects are evaluated. A larger staggered in-plane STT is found in the Mn3Ga case, while the STT in Mn3Al vanishes quickly away from the interface (similarly to STT in ferromagnetic MTJs). The roles are reversed for the TMR, which is practically 100% in the half-metallic Mn3Al-based MTJs (using the conservative definition) as opposed to 60% in the Mn3Ga case. The weak dependence on the exact interface reconstruction would suggest Mn3Ga–Mn3Al solid solutions as a possible route towards optimal trade-off of STT and TMR in the low-bias, low-temperature transport regime.http://dx.doi.org/10.1063/9.0000556
spellingShingle M. Stamenova
P. Stamenov
N. Baadji
Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al
AIP Advances
title Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al
title_full Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al
title_fullStr Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al
title_full_unstemmed Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al
title_short Ab initio comparison of spin-transport properties in MgO-spaced ferrimagnetic tunnel junctions based on Mn3Ga and Mn3Al
title_sort ab initio comparison of spin transport properties in mgo spaced ferrimagnetic tunnel junctions based on mn3ga and mn3al
url http://dx.doi.org/10.1063/9.0000556
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AT pstamenov abinitiocomparisonofspintransportpropertiesinmgospacedferrimagnetictunneljunctionsbasedonmn3gaandmn3al
AT nbaadji abinitiocomparisonofspintransportpropertiesinmgospacedferrimagnetictunneljunctionsbasedonmn3gaandmn3al