Publication detailsHickey, M.C. Ngo, D.-T. Lepadatu, S. Atkinson, D. , McGrouther, D. McVitie, S. & Marrows, C.H. (2010). Spin-transfer torque efficiency measured using a Permalloy nanobridge. Applied Physics Letters 97(20): 202505.
- Publication type: Journal Article
- ISSN/ISBN: 0003-6951, 1077-3118
- DOI: 10.1063/1.3520144
- Further publication details on publisher web site
- Durham Research Online (DRO) - may include full text
Author(s) from Durham
We report magnetoresistance, focused Kerr effect, and Lorentz microscopy experiments performed on a nanoscale Permalloy bridge connecting microscale pads. These pads can be switched from a parallel to antiparallel state through the application of small fields, causing a detectable magnetoresistance. We show that this switching field Hsw is modified by the application of a high current density (Jdc) through spin-transfer torque effects, caused by the spin-current interacting with the magnetization gradients generated by the device geometry, yielding an estimate for the spin-transfer torque efficiency ξ = dHsw/dJdc = 0.027±0.001 Oe/MA cm−2.