题目: Self-consistent determination of spin Hall angle and spin diffusion length in heavy metals

报告人：丁海峰

时间:2018年12月18日上午10点30分

地点:格致楼3016

摘要

The study of pure spin currents has attracted great recent interest as they carry information with minimal power dissipation. Spin Hall Angle (SHA) and spin diffusion length (SDL) are the key parameters in describing the spin-charge conversion which is the key issue in the generation, detection and application of pure spin currents. Despite their importance and many efforts devoted to quantify them, significant inconsistencies exist in the reported values for the same given material. We report a self-consistent method to quantify both SHA and SDL of nonmagnetic heavy metals by spin pumping with various ferromagnetic pumping sources. We remove the unwanted contamination, characterize the pure spin current with microwave photo-resistance effect and find that the pumped spin current suffers an interfacial spin loss (ISL) whose magnitude varies for different interfaces. With proper treating of the ISL effect, consistent values of SHA and SDL are obtained for both Pt and Pd regardless of the ferromagnet used.

In collaboration with K. Chen, S. Zhang (University of Arizona), L. Zhang, Z. Yuan (Beijing Normal University).

Ref. Science Advances, 4, (2018) eaat1670.

报告人简介

丁海峰南京大学6163银河net163am教授，博士生导师。2001年9月德国马克思普兰克微结构物理研究所和马丁-路德大学联合培养博士学位，2001年10月-2006年1月先后在德国马克思普兰克微结构物理研究所和美国阿贡国家实验室从事博士后研究。2006年2月至今为南京大学6163银河net163am教授、博士生导师。迄今发表SCI论文60余篇，作为第一或通讯作者发表3篇PRL，11篇PRB，3篇APL。