2008/03/18 by A. Deac, Alina M. Deac, Akio Fukushima +11 · 2 citations
Materials Science · Physics and Astronomy · #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #ZnO doping and properties #cond-mat.other
paper · pdf · doi:10.1038/nphys1036
6 figures 1 supplementary information file
arxiv created 2008/03/18 · openalex publication_date 2008/08/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
Spin-momentum transfer between a spin-polarized current and a ferromagnetic layer can induce steady-state magnetization precession, and has recently been proposed as a working principle for ubiquitous radio-frequency devices for radar and telecommunication applications. However, to-date, the development of industrially attractive prototypes has been hampered by the inability to identify systems which can provide enough power. Here, we demonstrate that microwave signals with device-compatible output power levels can be generated from a single magnetic tunnel junction with a lateral size of 100 nm, seven orders of magnitude smaller than conventional radio-frequency oscillators. We find that in MgO magnetic tunnel junctions the perpendicular torque induced by the spin-polarized current on the local magnetization can reach 25% of the in-plane spin-torque term, while exhibiting a different bias-dependence. Both findings contrast with the results obtained on all-metallic structures - previously investigated -, reflecting the fundamentally different transport mechanisms in the two types of structures.