Lee Won-Yong, Park No-Won, Kang Min-Sung, Kim Gil-Sung, Yoon Young-Gui, Lee Suheon, Choi Kwang-Yong, Kim Keun Soo, Kim Jin-Hyuk, Seong Maeng-Je, Kikkawa Takashi, Saitoh Eiji, Lee Sang-Kwon
Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea.
Deopartment of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea.
ACS Appl Mater Interfaces. 2021 Sep 22;13(37):45097-45104. doi: 10.1021/acsami.1c13180. Epub 2021 Sep 8.
A recent study found that magnetization curves for YFeO (YIG) slab and thick films (>20 μm thick) differed from bulk system curves by their longitudinal spin Seebeck effect in a Pt/YIG bilayer system. The deviation was due to intrinsic YIG surface magnetic anisotropy, which is difficult to adopt extrinsic surface magnetic anisotropy even when in contact with other materials on the YIG surface. This study experimentally demonstrates evidence for extrinsic YIG surface magnetic anisotropy when in contact with a diamagnetic graphene interlayer by observing the spin Seebeck effect, directly proving intrinsic YIG surface magnetic anisotropy interruption. We show the Pt/YIG bilayer system graphene interlayer role using large area single and multilayered graphenes using the longitudinal spin Seebeck effect at room temperature, and address the presence of surface magnetic anisotropy due to magnetic proximity between graphene and YIG layer. These findings suggest a promising route to understand new physics of spin Seebeck effect in spin transport.
最近的一项研究发现，在Pt/YIG双层系统中，YFeO（YIG）平板和厚膜（厚度大于20μm）的磁化曲线因其纵向自旋塞贝克效应而与体系统曲线不同。这种偏差是由于YIG的固有表面磁各向异性，即使YIG表面与其他材料接触，也很难采用外在表面磁各向异性。本研究通过观察自旋塞贝克效应，实验证明了与抗磁性石墨烯中间层接触时YIG外在表面磁各向异性的证据，直接证明了YIG固有表面磁各向异性的中断。我们在室温下利用纵向自旋塞贝克效应，使用大面积的单层和多层石墨烯展示了Pt/YIG双层系统中石墨烯中间层的作用，并探讨了由于石墨烯与YIG层之间的磁近邻效应而导致的表面磁各向异性的存在。这些发现为理解自旋输运中自旋塞贝克效应的新物理提供了一条有前景的途径。
