TY - JOUR
T1 - Analysis method of a spin-torque oscillator using dc resistance change during injection locking to an external microwave magnetic field
AU - Asam, Nagarjuna
AU - Suto, Hirofumi
AU - Tamaru, Shingo
AU - Sepehri-Amin, Hossein
AU - Bolyachkin, Anton
AU - Nakatani, Tomoya
AU - Zhou, Weinan
AU - Kubota, Hitoshi
AU - Sakuraba, Yuya
N1 - Funding Information:
This work was partially funded by the advanced storage research consortium (ASRC), Japan and JSPS KAKENHI Grant Nos. 17H06152 and 19K05257.
Publisher Copyright:
© 2021 Author(s).
PY - 2021/10/4
Y1 - 2021/10/4
N2 - Spin torque oscillators (STOs) that generate a persistent magnetization oscillation by spin-transfer torque are promising spintronic devices for various applications. In this study, we propose and experimentally demonstrate a method to characterize the magnetization dynamics of STOs using injection locking. By placing the STO near an antenna that generates a microwave magnetic field of a variable frequency, injection locking of the STO to the microwave field occurs when is in the locking range around the intrinsic oscillation frequency. During injection locking, the dc resistance of the STO exhibits a peak-and-valley dependence on W which originates from the modification of the magnetization trajectory induced by injection locking. Based on this principle, the oscillation frequency can be estimated by measuring the dc resistance change. Because this method does not require measuring the high-frequency magnetoresistance signal from the STO, which is used in the conventional method, it is advantageous in cases where the high-frequency magnetoresistance signal is undetectable or exhibits additional frequency components different from the oscillation frequency.
AB - Spin torque oscillators (STOs) that generate a persistent magnetization oscillation by spin-transfer torque are promising spintronic devices for various applications. In this study, we propose and experimentally demonstrate a method to characterize the magnetization dynamics of STOs using injection locking. By placing the STO near an antenna that generates a microwave magnetic field of a variable frequency, injection locking of the STO to the microwave field occurs when is in the locking range around the intrinsic oscillation frequency. During injection locking, the dc resistance of the STO exhibits a peak-and-valley dependence on W which originates from the modification of the magnetization trajectory induced by injection locking. Based on this principle, the oscillation frequency can be estimated by measuring the dc resistance change. Because this method does not require measuring the high-frequency magnetoresistance signal from the STO, which is used in the conventional method, it is advantageous in cases where the high-frequency magnetoresistance signal is undetectable or exhibits additional frequency components different from the oscillation frequency.
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U2 - 10.1063/5.0058847
DO - 10.1063/5.0058847
M3 - Article
AN - SCOPUS:85116932449
SN - 0003-6951
VL - 119
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 14
M1 - 142405
ER -