Current control of magnetic anisotropy via stress in a ferromagnetic metal waveguide
Journal
Physical Review B
Journal Volume
93
Journal Issue
14
Date Issued
2016
Author(s)
Abstract
Current control of magnetism, especially in multilayer thin films, hold great promise for applications in spintronics. Efficient control can be achieved using spin-orbit torques originating from either the spin Hall effect or the Rashba effect. In the context of spin waves, direct current pass through a heavy metal/ferromagnetic bilayer may be used to reduce/amplify damping or shift the resonant field. The effective field or damping introduced by the spin Hall or the Rashba effects depends on the current linearly, reversing the sign with a direct current in the opposite direction. The authors of this study report unexpected symmetric magnetic resonance shifts for spin waves passing through a CoFeB/Ta waveguide. This second-order effect arises from the dc modified magnetic anisotropy via anisotropic stress introduced between the substrate and the bilayer. Similar current-induced magnetoelastic effects may be relevant in many ferromagnetic heterostructures subject to large direct current.
Type
journal article