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arXiv · 1810.05674

Spin-Orbit Torque and Nernst Effect in Bi-Sb/Co Heterostructures

Niklas Roschewsky·Emily S. Walker·Praveen Gowtham·Sarah Muschinske·Frances Hellman·Seth R. Bank·Sayeef Salahuddin
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Abstract

Harmonic measurements of the longitudinal and transverse voltages in Bi-Sb/Co bilayers are presented. A large second harmonic voltage signal due to the ordinary Nernst effect is observed. In experiments where a magnetic field is rotated in the film plane, the ordinary Nernst effect shows the same angular dependence in the transverse voltage as the damping-like spin-orbit torque and in the longitudinal voltage as the unidirectional spin-Hall magneto-resistance respectively. Therefore, the ordinary Nernst effect can be a spurious signal in spin-orbit torque measurements, leading to an overestimation of the spin-Hall angle in topological insulators or semimetals.

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Niklas Roschewsky, Emily S. Walker, Praveen Gowtham, Sarah Muschinske, Frances Hellman, Seth R. Bank, Sayeef Salahuddin. 2018-10-12. Spin-Orbit Torque and Nernst Effect in Bi-Sb/Co Heterostructures. https://doi.org/10.1103/physrevb.99.195103

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