Generalized analysis of thermally activated domain-wall motion in Co/Pt multilayers

Bibliographic Details
Title: Generalized analysis of thermally activated domain-wall motion in Co/Pt multilayers
Authors: Emori, Satoru, Umachi, Chinedum K., Bono, David C., Beach, Geoffrey S. D.
Source: JMMM 378, 98 (2015)
Publication Year: 2014
Collection: Condensed Matter
Subject Terms: Condensed Matter - Materials Science
More Details: Thermally activated domain-wall (DW) motion driven by magnetic field and electric current is investigated experimentally in out-of-plane magnetized Pt(Co/Pt)$_3$ multilayers. We directly extract the thermal activation energy barrier for DW motion and observe the dynamic regimes of creep, depinning, and viscous flow. Further analysis reveals that the activation energy must be corrected with a factor dependent on the Curie temperature, and we derive a generalized Arrhenius-like equation governing thermally activated motion. By using this generalized equation, we quantify the efficiency of current-induced spin torque in assisting DW motion. Current produces no effect aside from Joule heating in the multilayer with 7-\AA\ thick Co layers, whereas it generates a finite spin torque on DWs in the multilayer with atomically thin 3-\AA\ Co layers. These findings suggest that conventional spin-transfer torques from in-plane spin-polarized current do not drive DWs in ultrathin Co/Pt multilayers.
Document Type: Working Paper
DOI: 10.1016/j.jmmm.2014.10.147
Access URL: http://arxiv.org/abs/1410.7685
Accession Number: edsarx.1410.7685
Database: arXiv
More Details
DOI:10.1016/j.jmmm.2014.10.147