Elphick, Kelvin, Yoshida, Kenta, Roy, Tufan et al. (9 more authors) (2021) Lattice Softening in Metastable bcc CoxMn100-x (001) Ferromagnetic Layers for a Strain-Free Magnetic Tunnel Junction. Physical Review Applied. 054052. ISSN 2331-7019
Abstract
In spintronics, one of the long-standing questions is why the MgO-based magnetic tunnel junction (MTJ) is almost the only option for achieving a large tunneling magnetoresistance (TMR) ratio at room temperature, although this is not as large as the theoretical prediction. This study focuses on the development of an almost strain-free MTJ using metastable bcc CoxMn100-x (Co − Mn) ferromagnetic films. We investigate the degree of crystallization in MTJs consisting of Co-Mn/MgO/Co-Mn in relation to their TMR ratios. Cross-section high resolution transmission electron microscopy reveals that almost consistent lattice constants of these layers for 66≤x ≤83 with large TMR ratios of 229% at room temperature, confirming the soft nature of the Co-Mn layer with some dislocations at the MgO/Co75Mn25 interfaces. Ab initio calculations confirm the crystalline deformation stability across a broad compositional range in Co-Mn, proving the advantage of a strain-free interface for much larger TMR ratios.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details |
Dates: |
|
Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Electronic Engineering (York) |
Depositing User: | Pure (York) |
Date Deposited: | 18 Nov 2021 12:00 |
Last Modified: | 26 Mar 2025 00:11 |
Published Version: | https://doi.org/10.1103/PhysRevApplied.16.054052 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1103/PhysRevApplied.16.054052 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:180602 |