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Title: Spin-torque ferromagnetic resonance based on current-induced impedance
Spin-torque ferromagnetic resonance (ST-FMR) has been widely used for measuring damping-like spin–orbit torques in magnetic bilayers. Typically, the ratio between the damping-like and field-like spin–orbit torques are extrapolated based on the ferromagnetic resonance line shapes. However, when the field-like spin–orbit torque is unknown, the line shape analysis may lead to errors in extrapolating the damping-like spin–orbit torque. Here, we propose a modified version of the ST-FMR that allows extrapolation of both damping-like and field-like torques independently. By introducing an alternating current to the sample, the RF impedance is modulated, allowing detection via the reflected microwave. We show that the extrapolated field-like and damping-like torques in Py/Pt samples are consistent with the technique measuring current-induced linewidth and resonance field change but have much better signal-to-noise ratio. Our proposed method paves a way for more accurate measurement of spin–orbit torques.  more » « less
Award ID(s):
2047118
PAR ID:
10572643
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Applied Physics Letters
Date Published:
Journal Name:
Applied Physics Letters
Volume:
125
Issue:
2
ISSN:
0003-6951
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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