Linear Phase Tuning of Spin Torque Oscillators Using In-Plane Microwave Fields
2014 (English)In: IEEE transactions on magnetics, ISSN 0018-9464, E-ISSN 1941-0069, Vol. 50, no 1, 1400104- p.Article in journal (Refereed) Published
We demonstrate numerically and analytically that a nano-pillar spin torque oscillator (STO), operating either with in-plane or out-ofplane free-layer precession, locks to a microwave field (H-ac) having the same frequency as the STO. By varying the spatial direction of the microwave field, we further show the preferred phase shift (Delta Phi(0)) between the STO and H-ac can be tuned in a linear fashion. We explain this phenomenon by using a magnetic-energy-based analysis. Our results provide a way to synchronize serially connected STOs by tuning the phase shift of each individual STO with external microwave field, which may enhance the locking efficiency, the locking range, and the output power of the serially connected STOs.
Place, publisher, year, edition, pages
2014. Vol. 50, no 1, 1400104- p.
Locking frequency, microwave field, phase lock, spin torque oscillator
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-141308DOI: 10.1109/TMAG.2013.2276665ISI: 000330026800019ScopusID: 2-s2.0-84904348413OAI: oai:DiVA.org:kth-141308DiVA: diva2:696647
QC 201402142014-02-142014-02-132014-02-14Bibliographically approved