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1. Magnetic force microscopy revealing long-range room temperature stable molecule bridge-induced magnetic ordering on magnetic tunnel junction (MTJ) pillars

   https://doi.org/10.1063/9.0000937  

   Tyagi, Pawan (March 2025, AIP Advances)

   Magnetic tunnel junctions (MTJs) can integrate novel single molecular device elements to overcome long-standing fabrication challenges, thus unlocking their novel potential. This study employs magnetic force microscopy (MFM) to demonstrate that organometallic molecules, when placed between two ferromagnetic electrodes along cross-junction shaped MTJ edges, dramatically altered the magnetic properties of the electrodes, affecting areas several hundred microns in size around the molecular junction vicinity at room temperature. These findings are supported by magnetic resonance and magnetometer studies on ∼7000 MTJ pillars. MFM on the pillar sample showed an almost complete disappearance of the magnetic contrast. The spatial magnetic image suggests that molecular channels significantly impacted the spin density of states in the ferromagnetic electrodes. This advancement in MTJ-based molecular devices paves the way for a new generation of commercially viable logic and memory devices controlled by molecular quantum states at near-room temperatures. 

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2. Advances in tissue engineering approaches for repairing and rehabilitating the myotendinous junction

   https://doi.org/10.1016/j.cobme.2024.100532  

   Shama, Kariman A; Turner, Mariah A; Broadaway, Harrison B; Aikman, Elizabeth L; Stoppel, Whitney L; Taylor, Brittany L (June 2024, Current Opinion in Biomedical Engineering)

   The myotendinous junction (MTJ) acts as a bridge between muscle and tendon; yet its high stiffness relative to muscle fibers renders the tissue susceptible to injuries due to eccentric loading disparities. The limited regenerative capacity of MTJ tissue and potential for postsurgical scarring and reinjury necessitates complementary therapeutics that can enhance cellular interactions, restore mechanical properties, and support tissue rehabilitation. This review explores various approaches to engineer the MTJ utilizing biomaterial scaffolds and cellularized materials that mimic structure and function. While biomimetic materials show promise, challenges remain due to the interface’s complexity and differing patient- and location-specific structure–function characteristics, necessitating further research to address these gaps. This review also highlights the importance of studying MTJ injuries in women’s health and craniofacial reconstruction. Furthermore, engineered MTJ models provide versatile platforms for investigating trauma and degeneration, thus offering potential for advancing research across multiple fields, shedding light on interactions at tissue interfaces, and shaping the future of MTJ rehabilitation. 

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3. Magnetic molecules lose identity when connected to different combinations of magnetic metal electrodes in MTJ-based molecular spintronics devices (MTJMSD)

   https://doi.org/10.1038/s41598-023-42731-9  

   Mutunga, Eva; D’Angelo, Christopher; Tyagi, Pawan (December 2023, Scientific Reports)

   Abstract Understanding the magnetic molecules’ interaction with different combinations of metal electrodes is vital to advancing the molecular spintronics field. This paper describes experimental and theoretical understanding showing how paramagnetic single-molecule magnet (SMM) catalyzes long-range effects on metal electrodes and, in that process, loses its basic magnetic properties. For the first time, our Monte Carlo simulations, verified for consistency with regards to experimental studies, discuss the properties of the whole device and a generic paramagnetic molecule analog (GPMA) connected to the combinations of ferromagnet-ferromagnet, ferromagnet-paramagnet, and ferromagnet-antiferromagnet metal electrodes. We studied the magnetic moment vs. magnetic field of GPMA exchange coupled between two metal electrodes along the exposed side edge of cross junction-shaped magnetic tunnel junction (MTJ). We also studied GPMA-metal electrode interfaces’ magnetic moment vs. magnetic field response. We have also found that the MTJ dimension impacted the molecule response. This study suggests that SMM spin at the MTJ exposed sides offers a unique and high-yield method of connecting molecules to virtually endless magnetic and nonmagnetic electrodes and observing unprecedented phenomena in the molecular spintronics field. 

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4. Radio-frequency assisted switching in perpendicular magnetic tunnel junctions

   https://doi.org/10.1038/s44306-026-00138-y  

   Hayward, Mark; Perna, Salvatore; d’Aquino, Massimiliano; Serpico, Claudio; Jung, Wonjoon; Dai, Chunhui; Braganca, Patrick M; Krivorotov, Ilya N (December 2026, npj Spintronics)

   Abstract Spin-transfer torque magnetic random-access memory (STT-MRAM) relies on nanoscale magnetic tunnel junctions (MTJs) as its fundamental building blocks. Next-generation STT-MRAM requires strategies that simultaneously improve switching energy efficiency and device endurance. Here, we present the first study of perpendicular STT-MRAM writing assisted by radio-frequency (RF) spin torque. We show that applying a small-amplitude RF pulse prior to a direct-current (DC) write pulse enhances the MTJ switching probability, with the efficiency gain increasing at lower RF frequencies. This RF+DC writing scheme enables shorter DC pulses, thereby improving device endurance. Analytical and numerical modeling qualitatively reproduces the experimental trends, while quantitative discrepancies indicate that realistic MTJ properties beyond idealized models play an important role in RF-assisted switching. 

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5. Earthquake clustering and stress inversion in the Mendocino Triple Junction region

   https://doi.org/10.1093/gji/ggag089  

   Hsu, Yu-Fang; Martínez-Garzón, Patricia; Trugman, Daniel T; Ben-Zion, Yehuda (April 2026, Geophysical Journal International)

   SUMMARY The Mendocino Triple Junction (MTJ), where the Gorda, North American and Pacific plates meet, is one of the most seismically active regions in California. The tectonic movements along the Mendocino transform fault zone (MTFZ), Gorda slab (GS) and northern San Andreas Fault systems (NSAF) lead to high background seismicity rates but relatively low aftershock productivity. To improve the understanding of earthquake processes in the area, we analyse relations between background seismicity, aftershock productivity and stress parameters. We apply the nearest-neighbour approach to investigate the spatial distributions and properties of background and clustered seismicity, and invert focal mechanisms of events in Voronoi cells for features of the deviatoric stress field. The results indicate that the intensity of background seismicity and aftershock productivity decrease with distance from the MTJ, defined here for simplicity as the hypocentre of the 1992 Mw 7.2 main shock. We also find that the stress regime is the most compressive in the area directly surrounding the MTJ. In the MTFZ and GS, the compressive stress decreases with increasing distance from the MTJ, correlating with the reduced aftershock productivity and background seismicity. In the NSAF, the observed relations between the stress, aftershock productivity and background seismicity are not clear, possibly due to crustal extension related to the slab window and elevated heat flow. Compared to the MTFZ and GS, the NSAF has a higher foreshock proportion, lower aftershock proportion and small-to-medium main shock magnitudes, indicating more swarm-like clusters in this region. The inverted stress regimes in the MTFZ and NSAF are dominated by strike-slip faulting. The GS exhibits mostly strike-slip and normal mechanisms despite the subduction environment, which may reflect slab bending and reactivation of pre-existing normal faults. 

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