English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We use micromagnetic simulations to map out and compare, the linear andauto-oscillating modes in constriction-based spin Hall nano-oscillators as afunction of applied magnetic field with varying magnitude and out-of-planeangle. We demonstrate that for all possible applied field configurations theauto-oscillations emerge from the localized linear modes of the constriction.For field directions tending towards the plane, these modes are of theso-called "edge" type, i.e. localized at the opposite sides of theconstriction. When the magnetization direction instead approaches the filmnormal, the modes transform to the so-called "bulk" type, i.e. localized insidethe constriction with substantially increased precession volume, consistentwith the re-distribution of the magnetic charges from the sides to the top andbottom surfaces of the constriction. In general, the threshold current of thecorresponding auto-oscillations increases with the applied field strength anddecreases with its out-of-plane angle, consistent with the behavior of theinternal field and in good agreement with a macrospin model. A quantitativeagreement is then achieved by taking into account the strongly non-uniformcharacter of the system via a mean-field approximation. Both the Oe field andthe spin transfer torque from the drive current increase the localization anddecrease the frequency of the observed mode. Furthermore, the anti-symmetric Oefield breaks the lateral symmetry, favoring the localized mode at one of thetwo constriction edges, in particular for large out-of-plane field angles wherethe threshold current is significantly increased and the edge demagnetizationis suppressed.

On the origin of magnetization auto-oscillations in constriction-based spin Hall nano-oscillators