Abstract
Recently magnetic tunnel junctions using two-dimensional MoS2 as nonmagnetic spacer have been fabricated, although their magnetoresistance has been reported to be quite low. This may be attributed to the use of permalloy electrodes, injecting current with a relatively small spin polarization. Here we evaluate the performance of MoS2-based tunnel junctions using Fe3Si Heusler alloy electrodes. Density functional theory and the non-equilibrium Green’s function method are used to investigate the spin injection efficiency (SIE) and the magnetoresistance (MR) ratio as a function of the MoS2 thickness. We find a maximum MR of ~300% with a SIE of about 80% for spacers comprising between 3 and 5 MoS2 monolayers. Most importantly, both the SIE and the MR remain robust at finite bias, namely MR > 100% and SIE > 50% at 0.7 V. Our proposed materials stack thus demonstrates the possibility of developing a new generation of performing magnetic tunnel junctions with layered two-dimensional compounds as spacers.
Highlights
Strong of the success of existing magnetic tunnel junctions (MTJs) based on the FeCoB/MgO stack[1,2] as magnetic sensors, there is a technological push towards the development of magnetoresistive devices, where the magnetization direction of the electrodes can be controlled with optical[3] or current-induced stimuli[4,5]
In the D03 structure (Fm3m) the A, B and C sites of Fe3Si are occupied by Fe ions, while Si is placed at the remaining octahedral-coordinated D site
In conclusion we have demonstrated that magnetic tunnel junctions based on Fe3Si Heusler alloy electrodes and MoS2 spacers may present advantages over the most conventional choices based on transition metals permalloy
Summary
Strong of the success of existing magnetic tunnel junctions (MTJs) based on the FeCoB/MgO stack[1,2] as magnetic sensors, there is a technological push towards the development of magnetoresistive devices, where the magnetization direction of the electrodes can be controlled with optical[3] or current-induced stimuli[4,5]. These may enable functionalities currently out of reach because of the intrinsic materials limitations of the Co-Fe system. Both remain robust as the bias potential is increased
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
