Han, Ki Hyuk Yun, Deok Hyun Jang, Seung-Hun Ahn, Jeong Ung Nah, Young-Jun Kim, YongJin Kang, Min-Gu Hong, Seokmin Koo, Hyun Cheol Lee, OukJae 2025-11-11T08:33:49Z 2025-11-11T08:33:49Z 2025-11-11 2025-10 https://pubs.kist.re.kr/handle/201004/153438 Spin-orbit torque (SOT) enables efficient control of magnetization via spin-orbit coupling effects, so that accurate quantification of its efficiency is crucial for the development of spin-orbit devices. Among various characterization techniques, spin-torque ferromagnetic resonance (ST-FMR) provides a powerful method to quantify SOT. However, conventional analysis methods-such as voltage ratio analysis and DC modulation-often suffer from the limited accuracy due to uncertainties in RF current estimation. In this study, we propose a voltage-based circuit analysis that directly utilizes the measured ST-FMR signals, including parasitic effects, such as RF power loss, modulation factors, and parasitic shunting. Self-consistent checks and measurements on various heterostructures confirm that our approach yields SOT efficiencies consistent with those obtained from conventional methods. Furthermore, substrate-dependent variations are resolved by applying parasitic correction, validating the robustness of our analysis. This work provides an accurate and practical methodology for evaluating SOT efficiency of spin-orbit materials. English American Institute of Physics Publising LLC Voltage-circuit analysis in spin-torque ferromagnetic resonance Article 10.1063/5.0293634 1 APL Materials, v.13, no.10 APL Materials 13 10 Y scie scopus 001599986100001 2-s2.0-105020020342 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Science & Technology - Other Topics Materials Science Physics Article MAGNETIC-PROPERTIES PERMEABILITY IMPACT