Giant Voltage-Controlled Magnetic Anisotropy in Strained Ir/FeCo/MgO Heterostructures

ORAL

Abstract

Contrary to current-controlled magnetic random access memory devices utilizing spin transfer torque (STT) or spin-orbit torques (SOT), voltage-induced magnetization switching can lead to a new paradigm enabling ultralow-power and high density instant-on nonvolatile magnetoelectric random access memory (MeRAM) devices. Employing ab initio electronic structure calculations we have investigated the effect of epitaxial strain on the voltage-controlled magnetic anisotropy (VCMA) behavior in Ir/FeCo/MgO heterostructures. We find that the magnetic anisotropy energy decreases linearly with electric field where the giant VCMA efficiency is in the range of -1742 to -1,000 fJ/(Vm) in agreement with recent experiments. Furthermore, we predict an electric-field-induced spin-reorientation which depends on epitaxial strain. These findings open interesting prospects for exploiting strain engineering and the appropriate heavy metal cap to harvest higher efficiency VCMA for the next-generation MeRAM devices.

*Supported by NSF ERC-TANMS Grant No. 1160504 and by NSF-PREM Grant No. DMR-1205734.

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Presenters

  • Sohee Kwon

    • Department of Physics and Astronomy, Cal State Univ - Northridge

Authors

  • Sohee Kwon

    • Department of Physics and Astronomy, Cal State Univ - Northridge

  • Xiang Li

    • Department of Electrical Engineering, University of California, Los Angeles

  • Pedram Khalili Amiri

    • Northwestern University

  • Kang Wang

    • University of California, Los Angeles
    • Univ of California - Los Angeles
    • Department of Electrical Engineering, University of California, Los Angeles
    • Department of Electrical Engineering, UCLA
    • University of California Los Angeles
    • UCLA
    • Department of Electrical Engineering, Univ of California - Los Angeles
    • Electrical and Computer Engineering, University of California, Los Angeles
    • Electrical Engineering, UCLA

  • Nicholas Kioussis

    • Department of Physics and Astronomy, Cal State Univ - Northridge
    • Physics and Astronomy Department, California State University, Northridge
    • Physics and Astronomy, California State University, Northridge
    • Physics and Astronomy, Cal state university northridge