| 报告题目 | FMR-Drive Pure Spin Transport in Metals and Magnetic Insulators |
| 报告人 | Prof. YANG Fengyuan |
| 报告人单位 | Department of Physics, Ohio State University |
| 报告时间 | 2017-07-10 |
| 报告地点 | 合肥微尺度物质科学国家实验室九楼会议室（9004） |
| 主办单位 | 合肥微尺度物质科学国家实验室、中国科学技术大学物理系 |
| 报告介绍 | 报告摘要：
Spintronics relies on the generation, transmission, manipulation, and detection of spin current mediated by itinerant charges or magnetic excitations. Ferromagnetic resonance (FMR) spin pumping is a powerful technique in understanding pure spin currents. Building on the high-quality Y3Fe5O12 (YIG) films grown by our UHV off-axis sputtering technique and the large inverse spin Hall effect (ISHE) signals enabled by these films [1], we have characterized pure spin currents in several classes of materials with different magnetic structures, including: nonmagnetic (NM) metals, ferromagnetic (FM) metals, nonmagnetic insulators, and antiferromagnetic (AF) insulators [2]. The spin Hall angles determined for a series of 3d, 4d, and 5d NM metals show that both atomic number and d-electron count play important roles in spin Hall physics. By inserting an insulating spacer of various materials between YIG and Pt, we are able to probe the mechanism of spin pumping and the spin propagation. More interestingly, we observed robust spin current from YIG to Pt across AF insulators, which initially enhances the ISHE signals and can transmit spin currents up to 100 nm thickness, demonstrating highly efficient spin transport through an AF insulator carried by magnetic excitations. This will open a wide range of new opportunities for spintronics. [1]. Wang, et al. Phys. Rev. B 88, 100406(R) (2013).
[2]. Du, et al. Phys. Rev. Lett. 111, 247202 (2013); Wang, et al. Phys. Rev. Lett. 112, 197201 (2014); Wang, et al. Phys. Rev. Lett. 113, 097202 (2014); Adur, et al. Phys. Rev. Lett. 113, 176601 (2014); Du, et al. Phys. Rev. B 90, 140407(R) (2014); Wang, et al. Phys. Rev. B 91, 220410(R) (2015); Brangham, et al. Phys. Rev. B 94, 054418 (2016); Wang, et al. Appl. Phys. Lett. 110, 062402 (2017). Kimling, et al. Phys. Rev. Lett. 118, 057201 (2017).
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