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Single-molecule magnets (SMMs) are pivotal in molecular spintronics, showing unique quantum behaviors that can advance spin-based technologies. By incorporating SMMs into magnetic tunnel junctions (MTJs), new possibilities emerge for low-power, energy-efficient data storage, memory devices and quantum computing. This study explores how SMMs influence spin-dependent transport in antiferromagnet-based MTJ molecular spintronic devices (MTJMSDs). We fabricated cross-junction MTJ devices with an antiferromagnetic Ta/FeMn bottom electrode and ferromagnetic NiFe/Ta top electrode, with a ∼2 nm AlOx layer, designed so that the AlOx barrier thickness at the junction intersection matched the SMM length, allowing them to act as spin channels bridging the two electrodes. Following SMM treatment, the MTJMSDs exhibited significant current enhancement, reaching a peak of 40 μA at 400 mV at room temperature. In contrast, bare MTJ junctions experienced a sharp current reduction, falling to the pA range at 0°C and remaining stable at lower temperatures—a suppression notably greater than in SMM-treated samples (Ref: Sankhi et al., Journal of Magnetism and Magnetic Materials, p. 172608, 2024). Additional vibration sample magnetometry on pillar shaped devices of same material stacks indicated a slight decrease in magnetic moment after incorporating SMMs, suggesting an effect on magnetic coupling of molecule with electrodes. Overall, this work highlights the promise of antiferromagnetic materials in optimizing MTJMSD devices and advancing molecular spintronics.
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Electrical control of the switching layer in perpendicular magnetic tunnel junctions with atomically thin Ir dusting
The use of magnetic tunnel junction (MTJ)-based devices constitutes an important basis of modern spintronics. However, the switching layer of an MTJ is widely believed to be an unmodifiable setup, instead of a user-defined option, posing a restriction to the function of spintronic devices. In this study, we realized a reliable electrical control of the switching layer in perpendicular MTJs with 0.1 nm Ir dusting. Specifically, a voltage pulse with a higher amplitude drives the magnetization switching of the MTJ's bottom electrode, while a lower voltage amplitude switches its top electrode. We discussed the origin of this controllability and excluded the possibility of back-hopping. Given the established studies on enhancing the voltage-controlled magnetic anisotropy effect by adopting Ir, we attribute this switching behavior to the significant diffusion of Ir atoms into the top electrode, which is supported by scanning transmission electron microscopy with atomic resolution.
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- PAR ID:
- 10528597
- Publisher / Repository:
- AIP
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 124
- Issue:
- 18
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0203048
