Angular harmonic Hall voltage and magnetoresistance measurements of Pt/FeCoB and Pt-Ti/FeCoB bilayers for spin Hall conductivity determination

作     者：Skowronski, Witold Grochot, Krzysztof Rzeszut, Piotr Lazarski, Stanislaw Gajoch, Grzegorz Worek, Cezary Kanak, Jaroslaw Stobiecki, Tomasz Langer, Jürgen Ocker, Berthold Vafaee, Mehran 

作者机构：AGH University of Science and Technology Institute of Electronics Al. Mickiewicza 30 Kraków30-059 Poland AGH University of Science and Technology Faculty of Physics and Applied Computer Science Al. Mickiewicza 30 Kraków30-059 Poland Singulus Technologies AG Hanauer Landstrasse 103 Kahl am Main63796 Germany 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2021年

核心收录：

主　　题：Spin Hall effect 

摘      要：Materials with significant spin-orbit coupling enable efficient spin-to-charge interconversion, which can be utilized in novel spin electronic devices. A number of elements, mainly heavy-metals (HM) have been identified to produce a sizable spin current (js), while supplied with a charge current (j), detected mainly in the neighbouring ferromagnetic (FM) layer. Apart from the spin Hall angle θSH = js/j, spin Hall conductivity (σSH) is an important parameter, which takes also the resistivity of the material into account. In this work, we present a measurement protocol of the HM/FM bilayers, which enables for a precise σSH determination. Static transport measurements, including resistivity and magnetization measurements are accompanied by the angular harmonic Hall voltage analysis in a dedicated low-noise rotating probe station. Dynamic characterization includes effective magnetization and magnetization damping measurement, which enable HM/FM interface absorption calculation. We validate the measurement protocol in Pt and Pt-Ti underlayers in contact with FeCoB and present the σSH of up to 3.3x105 S/m, which exceeds the values typically measured in other HM, such as W or Ta. Copyright © 2021, The Authors. All rights reserved.