Bimodal Spin Switch Emerging from Hybridized 2D MoS₂/Ferromagnet Interfaces.

Area of Science:

• Spintronics
• Materials Science
• 2D Semiconductors

Background:

• MRAM development historically focused on magnetic tunnel junctions with fixed spin sources.
• Two-dimensional (2D) semiconductors offer potential for interface tailoring in spin valve devices.
• Integrating 2D semiconductors with oxidation-prone spintronics materials presents significant challenges.

Purpose of the Study:

• To fabricate and evaluate spin devices using large-scale MoS2 directly grown on a ferromagnetic spin source.
• To explore spin manipulation opportunities arising from MoS2 hybridization with ferromagnetic electrodes.
• To investigate the impact of 2D semiconductor hybridization on spin transport properties.

Main Methods:

• Fabrication of spin devices with large-scale MoS2 directly grown on monocrystalline ferromagnetic spin sources.
• Experimental evaluation of spin transport properties, including tunnel magnetoresistance (TMR).
• Ab initio calculations to model the electronic band structure evolution of MoS2 upon hybridization.

Main Results:

• Achieved a substantial TMR value exceeding 65%, an order of magnitude higher than previous exfoliated 2D semiconductor devices.
• Observed a non-monotonic dependence of the spin signal on applied bias, including sign reversal.
• Ab initio calculations confirmed MoS2 band structure modulation by ferromagnetic hybridization, showing exchange-induced spin splitting and a bimodal spin response.

Conclusions:

• Direct integration of 2D semiconductors with ferromagnetic materials unlocks unique spin manipulation opportunities.
• Hybridization of MoS2 with ferromagnetic electrodes significantly enhances TMR values and introduces novel spin transport behaviors.
• This approach paves the way for advanced spintronic devices leveraging the properties of 2D semiconductors.