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  • Open Access

Underlying mechanism for exchange bias in single-molecule magnetic junctions

Yu-Hui Tang* and Bao-Huei Huang

  • Department of Physics, National Central University, Jung-Li 32001, Taiwan

  • *yhtang@cc.ncu.edu.tw
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Phys. Rev. Research 3, 033264 – Published 20 September, 2021

DOI: https://doi.org/10.1103/PhysRevResearch.3.033264

Abstract

Magnetic proximity has been observed in a variety of solid-state magnetic devices, but has been less discussed at the molecular scale. In this study, the magnetotransport calculation is carried out using the generalized Landau-Lifshitz-Gilbert (LLG) equation combined with density functional theory (DFT) and our self-developed junpy calculated spin-torque effect. Except for the current driven spin torque, which is a promising approach for magnetization switch in magnetic random access memory, the equilibrium fieldlike spin torque also plays a crucial role in the strain-controlled exchange bias with current-controlled magnetic coercivity in single-molecule magnetic junctions. The tight-binding model is further employed to clarify the critical role of the interfacial spin filter effect arising from the hybridization between the linker and Co apex. These multidisciplinary DFT+junpy+LLG results may provide important and practical implications in the dual control of magnetic proximity and magnetization switching in molecular spintronics at low temperature, either by tensile strain or via smaller applied current density of the order of MA/cm2.

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Phys. Rev. Research 3, 033264– Published 20 September, 2021
  • Received 1 May 2021
  • Revised 25 August 2021
  • Accepted 9 September 2021
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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