Decoherence and Mode Hopping in a Magnetic Tunnel Junction Based Spin Torque Oscillator
2012 (English)In: Physical Review Letters, ISSN 0031-9007, Vol. 108, no 20, 207203- p.Article in journal (Refereed) Published
We discuss the coherence of magnetic oscillations in a magnetic tunnel junction based spin torque oscillator as a function of the external field angle. Time-frequency analysis shows mode hopping between distinct oscillator modes, which arises from linear and nonlinear couplings in the Landau-Lifshitz-Gilbert equation, analogous to mode hopping observed in semiconductor ring lasers. These couplings and, therefore, mode hopping are minimized near the current threshold for the antiparallel alignment of free-layer with reference layer magnetization. Away from the antiparallel alignment, mode hopping limits oscillator coherence.
Place, publisher, year, edition, pages
2012. Vol. 108, no 20, 207203- p.
Polarized Current, Driven, Multilayers, Generation, Emission
IdentifiersURN: urn:nbn:se:kth:diva-96724DOI: 10.1103/PhysRevLett.108.207203ISI: 000304064000018ScopusID: 2-s2.0-84861533335OAI: oai:DiVA.org:kth-96724DiVA: diva2:532944
FunderSwedish Research CouncilKnut and Alice Wallenberg Foundation
QC 201206122012-06-122012-06-112012-06-12Bibliographically approved