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1. Electrically Controlled All‐Antiferromagnetic Tunnel Junctions on Silicon with Large Room‐Temperature Magnetoresistance

   https://doi.org/10.1002/adma.202312008  

   Shi, Jiacheng; Arpaci, Sevdenur; Lopez‐Dominguez, Victor; Sangwan, Vinod K; Mahfouzi, Farzad; Kim, Jinwoong; Athas, Jordan G; Hamdi, Mohammad; Aygen, Can; Arava, Hanu; et al (March 2024, Advanced Materials)

   Abstract Antiferromagnetic (AFM) materials are a pathway to spintronic memory and computing devices with unprecedented speed, energy efficiency, and bit density. Realizing this potential requires AFM devices with simultaneous electrical writing and reading of information, which are also compatible with established silicon‐based manufacturing. Recent experiments have shown tunneling magnetoresistance (TMR) readout in epitaxial AFM tunnel junctions. However, these TMR structures are not grown using a silicon‐compatible deposition process, and controlling their AFM order required external magnetic fields. Here are shown three‐terminal AFM tunnel junctions based on the noncollinear antiferromagnet PtMn₃, sputter‐deposited on silicon. The devices simultaneously exhibit electrical switching using electric currents, and electrical readout by a large room‐temperature TMR effect. First‐principles calculations explain the TMR in terms of the momentum‐resolved spin‐dependent tunneling conduction in tunnel junctions with noncollinear AFM electrodes. 

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2. Giant Spin-flop magnetoresistance in a collinear antiferromagnetic tunnel junction

   https://doi.org/10.1038/s41467-025-62695-w  

   Xu, Shijie; Zhang, Zhizhong; Mahfouzi, Farzad; Huang, Yan; Cheng, Houyi; Dai, Bingqian; Kim, Jinwoong; Zhu, Daoqian; Cai, Wenlong; Shi, Kewen; et al (December 2025, Nature Communications)

   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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3. Prospects for Antiferromagnetic Spintronic Devices

   https://doi.org/10.1146/annurev-matsci-080222-030535  

   Khalili_Amiri, Pedram; Phatak, Charudatta; Finocchio, Giovanni (April 2024, Annual Review of Materials Research)

   This article examines recent advances in the field of antiferromagnetic spintronics from the perspective of potential device realization and applications. We discuss advances in the electrical control of antiferromagnetic order by current-induced spin–orbit torques, particularly in antiferromagnetic thin films interfaced with heavy metals. We also review possible scenarios for using voltage-controlled magnetic anisotropy as a more efficient mechanism to control antiferromagnetic order in thin films with perpendicular magnetic anisotropy. Next, we discuss the problem of electrical detection (i.e., readout) of antiferromagnetic order and highlight recent experimental advances in realizing anomalous Hall and tunneling magnetoresistance effects in thin films and tunnel junctions, respectively, which are based on noncollinear antiferromagnets. Understanding the domain structure and dynamics of antiferromagnetic materials is essential for engineering their properties for applications. For this reason, we then provide an overview of imaging techniques as well as micromagnetic simulation approaches for antiferromagnets. Finally, we present a perspective on potential applications of antiferromagnets for magnetic memory devices, terahertz sources, and detectors. 

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4. Observation of current-induced switching in non-collinear antiferromagnetic IrMn3 by differential voltage measurements

   https://doi.org/10.1038/s41467-021-24237-y  

   Arpaci, Sevdenur; Lopez-Dominguez, Victor; Shi, Jiacheng; Sánchez-Tejerina, Luis; Garesci, Francesca; Wang, Chulin; Yan, Xueting; Sangwan, Vinod K.; Grayson, Matthew A.; Hersam, Mark C.; et al (December 2021, Nature Communications)

   Abstract There is accelerating interest in developing memory devices using antiferromagnetic (AFM) materials, motivated by the possibility for electrically controlling AFM order via spin-orbit torques, and its read-out via magnetoresistive effects. Recent studies have shown, however, that high current densities create non-magnetic contributions to resistive switching signals in AFM/heavy metal (AFM/HM) bilayers, complicating their interpretation. Here we introduce an experimental protocol to unambiguously distinguish current-induced magnetic and nonmagnetic switching signals in AFM/HM structures, and demonstrate it in IrMn 3 /Pt devices. A six-terminal double-cross device is constructed, with an IrMn 3 pillar placed on one cross. The differential voltage is measured between the two crosses with and without IrMn 3 after each switching attempt. For a wide range of current densities, reversible switching is observed only when write currents pass through the cross with the IrMn 3 pillar, eliminating any possibility of non-magnetic switching artifacts. Micromagnetic simulations support our findings, indicating a complex domain-mediated switching process. 

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5. Néel spin-orbit torque in antiferromagnetic quantum spin and anomalous Hall insulators

   https://doi.org/10.1038/s41467-025-63171-1  

   Tang, Junyu; Zhang, Hantao; Cheng, Ran (August 2025, Nature Communications)

   Interplay between topological electrons and magnetic ordering enables efficient electrical control of magnetism. We extend the Kane-Mele model to include the exchange coupling to a collinear antiferromagnetic (AFM) order, which allows the system to exhibit the quantum anomalous Hall and quantum spin Hall effects in the absence of a net magnetization. These topological phases support a staggered Edelstein effect through which an applied electric field can generate opposite non-equilibrium spins on the two AFM sublattices, realizing the Néel-type spin-orbit torque (NSOT). Contrary to known NSOTs in AFM metals driven by conduction currents, our NSOT arises from pure adiabatic currents devoid of Joule heating, while being a bulk effect not carried by the edge currents. By virtue of the NSOT, the electric field of a microwave can drive the AFM resonance with a remarkably high efficiency, outpacing the magnetic field-induced AFM resonance by orders of magnitude in terms of power absorption. 

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