Determination of spin torque efficiencies in heterostructures with perpendicular magnetic anisotropy
We report that by measuring a current-induced hysteresis loop shift versus in-plane bias magnetic field, the spin-Hall effect (SHE) contribution of the current-induced effective field per current density χ[subscript SHE] can be estimated for Pt- and Ta-based magnetic heterostructures with perpendicu...
Main Authors: | , , , |
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Other Authors: | |
Format: | Article |
Language: | English |
Published: |
American Physical Society,
2016-04-15T14:48:16Z.
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Subjects: | |
Online Access: | Get fulltext |
Summary: | We report that by measuring a current-induced hysteresis loop shift versus in-plane bias magnetic field, the spin-Hall effect (SHE) contribution of the current-induced effective field per current density χ[subscript SHE] can be estimated for Pt- and Ta-based magnetic heterostructures with perpendicular magnetic anisotropy. We apply this technique to a Pt-based sample with its ferromagnetic (FM) layer being wedged deposited and discover an extra effective field contribution χ[subscript Wedged] due to the asymmetric nature of the deposited FM layer. We confirm the correlation between χ[subscript Wedged] and the asymmetric depinning process in FM layer during magnetization switching by magneto-optical Kerr microscopy. These results indicate the possibility of engineering deterministic spin-orbit torque switching by controlling the symmetry of domain expansion through the materials growth process. National Science Foundation (U.S.) (NSF-ECCS-1408172) |
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