Free- and reference-layer magnetization modes vs.~in-plane magnetic field in a magnetic tunnel junction with perpendicular magnetic easy axis
2016 (English)In: Physical Review B Condensed Matter, ISSN 0163-1829, E-ISSN 1095-3795Article in journal (Other (popular science, discussion, etc.)) Accepted
We study the magnetodynamic modes of a magnetic tunnel junction with perpendicular magnetic easy axis (p-MTJ) in in-plane magnetic fields using device-level ferromagnetic resonance spectroscopy. We compare our experimental results to those of micromagnetic simulations of the entire p-MTJ. Using an iterative approach to determine the material parameters that best fit our experiment, we find excellent agreement between experiments and simulations in both the static magnetoresistance and magnetodynamics in the free and reference layers. From the micromagnetic simulations, we determine the spatial mode profiles, the localization of the modes and, as a consequence, their distribution in the frequency domain due to the inhomogeneous internal field distribution inside the p-MTJ under different applied field regimes. We also conclude that the excitation mechanism is a combination of the microwave voltage modulated perpendicular magnetic anisotropy, the microwave Oersted field, and the spin-transfer torque generated by the microwave current.
Place, publisher, year, edition, pages
American Physical Society , 2016.
Condensed Matter Physics
Research subject Materials Science and Engineering; Physics
IdentifiersURN: urn:nbn:se:kth:diva-191175OAI: oai:DiVA.org:kth-191175DiVA: diva2:955244
FunderSwedish Foundation for Strategic Research
QC 201608292016-08-242016-08-242016-08-29Bibliographically approved