Investigation of magnetic droplet solitons using x-ray holography with extended referencesShow others and affiliations
2018 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 8, article id 11533Article in journal (Refereed) Published
Abstract [en]
A dissipative magnetic soliton, or magnetic droplet, is a structure that has been predicted to exist within a thin magnetic layer when non-linearity is balanced by dispersion, and a driving force counteracts the inherent damping of the spin precession. Such a soliton can be formed beneath a nano-contact (NC) that delivers a large spin-polarized current density into a magnetic layer with perpendicular magnetic anisotropy. Although the existence of droplets has been confirmed from electrical measurements and by micromagnetic simulations, only a few attempts have been made to directly observe the magnetic landscape that sustains these structures, and then only for a restricted set of experimental parameter values. In this work we use and x-ray holography technique HERALDO, to image the magnetic structure of the [ Co/ Ni] x4 multilayer within a NC orthogonal pseudo spin-valve, for different range of magnetic fields and injected electric currents. The magnetic configuration imaged at -33 mA and 0.3 T for devices with 90 nm NC diameter reveals a structure that is within the range of current where the droplet soliton exist based on our electrical measurements and have it is consistent with the expected size of the droplet (similar to 100 nm diameter) and its spatial position within the sample. We also report the magnetisation configurations observed at lower DC currents in the presence of fields (0-50 mT), where it is expected to observe regimes of the unstable droplet formation.
Place, publisher, year, edition, pages
Nature Publishing Group , 2018. Vol. 8, article id 11533
National Category
Other Physics Topics
Identifiers
URN: urn:nbn:se:kth:diva-233289DOI: 10.1038/s41598-018-29856-yISI: 000440411300018PubMedID: 30069062Scopus ID: 2-s2.0-85050962853OAI: oai:DiVA.org:kth-233289DiVA, id: diva2:1239409
Funder
Swedish Foundation for Strategic Research EU, European Research Council, 307144Swedish Research CouncilKnut and Alice Wallenberg Foundation
Note
QC 20180816
2018-08-162018-08-162024-03-18Bibliographically approved