Phase-locked spin torque oscillators: Impact of device variability and time delay
2007 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 101, no 9, 09A503- p.Article in journal (Refereed) Published
We have carried out detailed Landau-Lifshitz-Gilbert simulations of pairs of serially connected spin torque oscillators (STOs) in parallel with a resistive load. To study the impact of realistic process variations on STO synchronization we let the two STOs have different in-plane anisotropy fields (H-k). The simulation also provides for a time delay (tau). We construct a phase diagram of the STO synchronization as a function of H-k and direct current (I-dc) at different tau. The phase diagram turns out to be quite rich with different types of synchronized precession modes. While the synchronized state is originally very sensitive to STO process variations and can only sustain up to 4% H-k variation, the addition of a small time delay dramatically improves its robustness and allows as much as 145% H-k variation in the entire out-of-plane precession regime.
Place, publisher, year, edition, pages
2007. Vol. 101, no 9, 09A503- p.
polarized current, co/cu/co pillars, driven, dynamics, locking
Condensed Matter Physics
IdentifiersURN: urn:nbn:se:kth:diva-16640DOI: 10.1063/1.2670045ISI: 000246567900114ScopusID: 2-s2.0-34248585293OAI: oai:DiVA.org:kth-16640DiVA: diva2:334682
Conference: 10th Joint Magnetism and Magnetic Materials Conference/International Magnetics Conference. Baltimore, MD. JAN 07-11, 2007 2010-08-052010-08-052011-09-12Bibliographically approved