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A spin torque meter with magnetic facet domains.

ABSTRACT: Current-induced magnetic domain wall (DW) motion is an important operating principle of spintronic devices. Injected current generates spin torques (STs) on the DWs in two ways. One is the spin transfer from magnetic domains to the walls by the current flowing in the magnet. Current flow in attached heavy metals also generates another ST because of the spin-Hall effect. Both phenomena explain the wall motions well; therefore, their respective contribution is an important issue. Here, we show the simultaneous measurement of both torques by using magnetic facet domains that form mountain-shaped domains with straight walls. When the STs and the external magnetic field push the walls in opposite directions, the walls should have equilibrium angles to create balanced states. Such angles can be modulated by an additional in-plane magnetic field. Angle measurements distinguish the STs because each torque has a distinct mechanism related to the DW structure.

SUBMITTER: Moon KW

PROVIDER: S-EPMC6141574 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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A spin torque meter with magnetic facet domains.

Moon Kyoung-Woong KW Kim Changsoo C Yoon Jungbum J Choi Jun Woo JW Kim Dong-Ok DO Song Kyung Mee KM Kim Dongseuk D Chun Byong Sun BS Hwang Chanyong C

Nature communications 20180917 1

Current-induced magnetic domain wall (DW) motion is an important operating principle of spintronic devices. Injected current generates spin torques (STs) on the DWs in two ways. One is the spin transfer from magnetic domains to the walls by the current flowing in the magnet. Current flow in attached heavy metals also generates another ST because of the spin-Hall effect. Both phenomena explain the wall motions well; therefore, their respective contribution is an important issue. Here, we show the ...[more]

PMID: 30224700

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