Layer thickness dependence of the current-induced effective field vector in Ta|CoFeB|MgO

Current-induced effective magnetic fields can provide efficient ways of electrically manipulating the magnetization of ultrathin magnetic heterostructures. Two effects, known as the Rashba spin orbit field and the spin Hall spin torque, have been reported to be responsible for the generation of the...

Full description

Saved in:
Bibliographic Details
Published in:Nature materials 2013-03, Vol.12 (3), p.240-245
Main Authors: Kim, Junyeon, Sinha, Jaivardhan, Hayashi, Masamitsu, Yamanouchi, Michihiko, Fukami, Shunsuke, Suzuki, Tetsuhiro, Mitani, Seiji, Ohno, Hideo
Format: Article
Language:English
Subjects:
639/301/119/995
639/301/119/997
Biomaterials
Condensed Matter Physics
Electric currents
Electronics
Heterostructures
Landscapes
Magnetic fields
Magnetism
Magnetization
Materials Science
Mathematical analysis
Nanotechnology
Optical and Electronic Materials
Orbits
Tantalum
Vectors (mathematics)
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Current-induced effective magnetic fields can provide efficient ways of electrically manipulating the magnetization of ultrathin magnetic heterostructures. Two effects, known as the Rashba spin orbit field and the spin Hall spin torque, have been reported to be responsible for the generation of the effective field. However, a quantitative understanding of the effective field, including its direction with respect to the current flow, is lacking. Here we describe vector measurements of the current-induced effective field in Ta|CoFeB|MgO heterostructrures. The effective field exhibits a significant dependence on the Ta and CoFeB layer thicknesses. In particular, a 1 nm thickness variation of the Ta layer can change the magnitude of the effective field by nearly two orders of magnitude. Moreover, its sign changes when the Ta layer thickness is reduced, indicating that there are two competing effects contributing to it. Our results illustrate that the presence of atomically thin metals can profoundly change the landscape for controlling magnetic moments in magnetic heterostructures electrically. The control and manipulation of the magnetization of thin metallic films by means of an electric current is a promising strategy for ensuring that potential spintronic applications are energy efficient. It is now shown that large changes in the current-induced magnetic field can arise as a result of varying the thickness of the Ta layer in Ta|CoFeB|MgO heterostructures.
ISSN:1476-1122
1476-4660
DOI:10.1038/nmat3522