Interface-Assisted Room-Temperature Magnetoresistance in Cu-Phenalenyl-Based Magnetic Tunnel Junctions

Abstract

Delocalized carbon-based radical species with unpaired spin, such as the phenalenyl (PLY) radical, have opened avenues for developing multifunctional organic spintronic devices. Using direct laser writing and in situ deposition, we successfully fabricated Cu-PLY-and Zn-PLY-based organic magnetic tunnel junctions (OMTJs) with improved morphology and a reduced junction area of 3 × 8 μm 2 . The nonlinear and weakly temperature-dependent current−voltage (I−V) characteristics in combination with the low organic barrier height suggest tunneling as the dominant transport mechanism in the structurally and dimensionally optimized OMTJs. Cu-PLY-based OMTJs show significant magnetoresistance up to 14% at room temperature due to the formation of hybrid states at the metal−molecule interfaces called "spinterface", which reveals the importance of spin-dependent interfacial modification in OMTJs' design. Additionally, at high bias, in the absence of a magnetic field, OMTJ shows stable voltage-driven resistive switching. Cu-PLY having spin 1/2 with net magnetic moment demonstrates magnetic hardening between the surface molecule at the Co interface and gives rise to stable MR, which suggests its use as a feasible and scalable platform for building molecular-scale quantum memristors and processors.

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

“…In addition to our direct observations, other researchers’ work also provides evidence that any molecule directly connected to ferromagnetic electrodes undergoes dramatic changes. Recently, experimental studies showed that the hybridization of Cu-phenalenyl molecule and cobalt electrode energy states yields net magnetic moment on the molecules (with 1/2 spin state) near the interface at room temperature 47 . Spinterface, the interface between molecules and the magnetic electrodes, has started taking the form of a sub-branch in spintronics due to a spin-filtering-like phenomenon impacting the molecules and magnetic electrodes simultaneously 48 .…”

Enhanced Shubnikov–de Haas Oscillations in High Mobility InAlN/GaN Two-Dimensional Electron Gas

“…Transport properties serve as a crucial tool to understand the scattering mechanisms in the two-dimensional electron gas (2DEG) channel effectively. Various characterization techniques have been employed to ensure the production of high-quality samples. − Magnetoresistance measurements in quantum transport serve as a powerful tool for characterizing compound semiconductors, facilitating a deeper understanding of their electronic properties. − Quantum oscillations and their scattering phenomena have been extensively explored in various GaN based heterostructures. ,,− However, the quantum transport behaviors in this high-mobility InAlN/GaN heterostructure have not been widely reported. In particular, study on the InAlN/GaN 2DEG systems with high mobility remains a long-standing challenge due to growth challenges.…”