Magnetite is a half-metal with a high Curie temperature of 858 K, making it a promising candidate for magnetic tunnel junctions (MTJs). Yet, initial efforts to exploit its half metallic nature in Fe 3 O 4 /MgO/Fe 3 O 4 MTJ structures have been far from promising. Finding suitable barrier layer materials, which keep the half metallic nature of Fe 3 O 4 at the interface between Fe 3 O 4 layers and barrier layer, is one of main challenges in this field. Two-dimensional (2D) materials may be good candidates for this purpose. Molybdenum disulfide (MoS 2) is a transition metal dichalcogenide (TMD) semiconductor with distinctive electronic, optical, and catalytic properties. Here, we show based on the first principle calculations that Fe 3 O 4 keeps a nearly fully spin polarized electron band at the interface between MoS 2 and Fe 3 O 4. We also present the first attempt to fabricate the Fe 3 O 4 /MoS 2 /Fe 3 O 4 MTJs. A clear tunneling magnetoresistance (TMR) signal was observed below 200 K. Thus, our experimental and theoretical studies indicate that MoS 2 can be a good barrier material for Fe 3 O 4 based MTJs. Our calculations also indicate that junctions incorporating monolayer or bilayer MoS 2 are metallic.
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