2016/04/24 by Yun Kang, Kang, Yun, Hai Zhong +24
Engineering · Physics and Astronomy · #FOS: Physical sciences #Magnetic properties of thin films #Magneto-Optical Properties and Applications #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.1604.07025
openalex publication_date 2016/04/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Spin pumping in Yttrium-iron-garnet (YIG)/nonmagnetic-metal (NM) layer systems under ferromagnetic resonance (FMR) conditions is a popular method of generating spin current in the NM layer. A good understanding of the spin current source is essential in extracting spin Hall angle of the NM and in potential spintronics applications. It is widely believed that spin current is pumped from precessing YIG magnetization into NM layer. Here, by combining microwave absorption and DC-voltage measurements on YIG/Pt and YIG/NM1/NM2 (NM1=Cu or Al, NM2=Pt or Ta), we unambiguously showed that spin current in NM came from the magnetized NM surface (in contact with YIG) due to the magnetic proximity effect (MPE), rather than the precessing YIG magnetization. This conclusion is reached through our unique detecting method where the FMR microwave absorption of the magnetized NM surface, hardly observed in the conventional FMR experiments, was greatly amplified when the electrical detection circuit was switched on.