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Abstract Antiferromagnetic (AFM) spintronics has emerged as a subfield of spintronics, where an AFM Néel vector is used as a state variable. Efficient electric control and detection of the Néel vector are critical for spintronic applications. This review article features fundamental properties of AFM tunnel junctions (AFMTJs) as spintronic devices where such electric control and detection can be realized. We emphasize critical requirements for observing a large tunneling magnetoresistance (TMR) effect in AFMTJs with collinear and noncollinear AFM electrodes, such as a momentum-dependent spin polarization and Néel spin currents. We further discuss spin torques in AFMTJs that are capable of Néel vector switching. Overall, AFMTJs have potential to become a new standard for spintronics providing larger magnetoresistive effects, few orders of magnitude faster switching speed, and much higher packing density than conventional magnetic tunnel junctions (MTJs).
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This content will become publicly available on December 1, 2026
Giant Spin-flop magnetoresistance in a collinear antiferromagnetic tunnel junction
Collinear antiferromagnetic (AFM) materials have the unique promise of no stray fields, displaying ultrafast dynamics, and being robust against perturbation fields which motivate the extensive research of antiferromagnetic spintronics. However, the detection of antiferromagnetic order poses formidable challenges. Here, we report the electrical detection of colinear antiferromagnetism in all-epitaxial RuO2/MgO/RuO2 tunnel junctions (TJ) using spin-flop tunneling anisotropic magnetoresistance (TAMR). We measured a TAMR ratio of around 60% at room temperature, which arises from the switching between the parallel and perpendicular configurations of the adjacent collinear AFM state. Furthermore, we carried out angular-dependent measurements using this antiferromagnetic tunnel junction (AFM-TJ) and showed that the magnitude of anisotropic longitudinal magnetoresistance in the AFM-TJ can be controlled by the direction of an external magnetic field. First principles electronic structure calculations corroborate that the collinear antiferromagnetic TJ may produce a substantially large TAMR ratio. The emergence of resonant interfacial states, combined with the tunneling transmission through the MgO barrier and the substantial spin-orbit coupling (SOC) strength of Ru, especially when augmented by oxygen doping, leads to the significant enhancement observed in the tunneling anisotropic magnetoresistance (TAMR). Our work not only propels antiferromagnetic materials to the forefront of spintronic device innovation but also unveils a novel paradigm for electrically controlled antiferromagnetic spintronics, auguring transformative advancements in high-speed, low-energy information devices.
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- PAR ID:
- 10682577
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 16
- Issue:
- 1
- ISSN:
- 2041-1723
- Page Range / eLocation ID:
- 8370
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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