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arXiv · 1911.05487

Impact of the crystal orientation on spin-orbit torques in Fe/Pd bilayers

Ankit Kumar·Nilamani Behera·Rahul Gupta·Sajid Husain·Henry Stopfel·Vassilios Kapaklis·Rimantas Brucas·Peter Svedlindh
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Abstract

Spin-orbit torques in ferromagnetic (FM)/non-magnetic (NM) heterostructures offer more energy-efficient means to realize spin-logic devices; however, their strengths are determined by the heterostructure interface. This work examines crystal orientation impact on the spin-orbit torque efficiency in different Fe/Pd bilayer systems. Spin torque ferromagnetic measurements evidence that the damping-like torque efficiency is higher in epitaxial than in polycrystalline bilayer structures while the field-like torque is negligible in all bilayer structures. The strength of the damping-like torque decreases with deterioration of the bilayer epitaxial quality. The present finding provides fresh insight for the enhancement of spin-orbit torques in magnetic heterostructures.

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Ankit Kumar, Nilamani Behera, Rahul Gupta, Sajid Husain, Henry Stopfel, Vassilios Kapaklis, Rimantas Brucas, Peter Svedlindh. 2019-11-13. Impact of the crystal orientation on spin-orbit torques in Fe/Pd bilayers. https://doi.org/10.1088/1361-6463/ab8ed9

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