TY - JOUR
T1 - Dynamic detection of current-induced spin-orbit magnetic fields
AU - Chen, L.
AU - Islinger, R.
AU - Stigloher, J.
AU - Decker, M. M.
AU - Kronseder, M.
AU - Schuh, D.
AU - Bougeard, D.
AU - Weiss, D.
AU - Back, C. H.
N1 - Publisher Copyright:
© 2021 American Physical Society
PY - 2021/7/1
Y1 - 2021/7/1
N2 - Current-induced spin-orbit torques (SOTs) in ferromagnet/nonmagnetic metal heterostructures open vast possibilities to design spintronic devices to store, process, and transmit information in a simple architecture. It is a central task to search for efficient SOT devices, and to quantify the magnitude as well as the symmetry of current-induced spin-orbit magnetic fields (SOFs). Here, we report an approach to determine the SOFs based on magnetization dynamics by means of time-resolved magneto-optic Kerr microscopy. A microwave current in a narrow Fe/GaAs (001) stripe generates an Oersted field as well as SOFs due to the reduced symmetry at the Fe/GaAs interface, and excites standing spin wave (SSW) modes because of the lateral confinement. Due to their different symmetries, the SOFs and the Oersted field generate distinctly different mode patterns. Thus, it is possible to determine the magnitude of the SOFs from an analysis of the shape of the SSW patterns. Specifically, this method, which is conceptually different from previous approaches based on line shape analysis, is phase independent and self-calibrated. It can be used to measure the current-induced SOFs in other material systems, e.g., ferromagnetic metal/nonmagnetic metal heterostructures.
AB - Current-induced spin-orbit torques (SOTs) in ferromagnet/nonmagnetic metal heterostructures open vast possibilities to design spintronic devices to store, process, and transmit information in a simple architecture. It is a central task to search for efficient SOT devices, and to quantify the magnitude as well as the symmetry of current-induced spin-orbit magnetic fields (SOFs). Here, we report an approach to determine the SOFs based on magnetization dynamics by means of time-resolved magneto-optic Kerr microscopy. A microwave current in a narrow Fe/GaAs (001) stripe generates an Oersted field as well as SOFs due to the reduced symmetry at the Fe/GaAs interface, and excites standing spin wave (SSW) modes because of the lateral confinement. Due to their different symmetries, the SOFs and the Oersted field generate distinctly different mode patterns. Thus, it is possible to determine the magnitude of the SOFs from an analysis of the shape of the SSW patterns. Specifically, this method, which is conceptually different from previous approaches based on line shape analysis, is phase independent and self-calibrated. It can be used to measure the current-induced SOFs in other material systems, e.g., ferromagnetic metal/nonmagnetic metal heterostructures.
UR - http://www.scopus.com/inward/record.url?scp=85111631708&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.104.014425
DO - 10.1103/PhysRevB.104.014425
M3 - Article
AN - SCOPUS:85111631708
SN - 2469-9950
VL - 104
JO - Physical Review B
JF - Physical Review B
IS - 1
M1 - 014425
ER -