Effect of Temperature on Magnetic Solitons Induced by Spin-Transfer Torque

Lendínez, Sergi; Hang, Jing; Vélez, Saül; Hernández, J. M.; Backes, Dirk; Kent, Andrew D.; Maciá, Ferran

doi:10.1103/physrevapplied.7.054027

Cited by 19 publications

(27 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To excite a droplet in a ferromagnetic layer with PMA using a spin polarized current in a nanocontact, the spin-transfer torque must compensate the damping. There is a threshold current that depends on the NC size, the magnetization, the spin polarization of the current, and the external field 21,26,28,38 . For currents above the threshold, the magnetization in the NC forms a droplet state in a process that can take less than a nanosecond 39 .…”

Section: Creation Processmentioning

confidence: 99%

Generation and stability of dynamical skyrmions and droplet solitons

Statuto¹,

Hernández²,

Kent³

et al. 2018

Nanotechnology

Self Cite

View full text Add to dashboard Cite

A spin-polarized current in a nanocontact to a magnetic film can create collective magnetic oscillations by compensating the magnetic damping. In particular, in materials with uniaxial magnetic anisotropy, droplet solitons have been observed-a self-localized excitation consisting of partially reversed magnetization that precesses coherently in the nanocontact region. It is also possible to generate topological droplet solitons, known as dynamical skyrmions (DSs). Here, we show that spin-polarized current thresholds for DS creation depend not only on the material's parameters but also on the initial magnetization state and the rise time of the spin-polarized current. We study the conditions that promote either droplet or DS formation and describe their stability in magnetic films without Dzyaloshinskii-Moriya interactions. The Oersted fields from the applied current, the initial magnetization state, and the rise time of the injected current can determine whether a droplet or a DS forms. DSs are found to be more stable than droplets. We also discuss electrical characteristics that can be used to distinguish these magnetic objects.

show abstract

Section: Creation Processmentioning

confidence: 99%

Generation and stability of dynamical skyrmions and droplet solitons

Statuto¹,

Hernández²,

Kent³

et al. 2018

Nanotechnology

Self Cite

View full text Add to dashboard Cite

show abstract

“…To date, all the experimental studies of the magnetic droplet solitons have been performed in conventional NC-STNOs driven by spin-polarized electric current [14,[16][17][18][19][20][21], where the damping is compensated only locally, and therefore the generated solitons are strongly localized in the region of the nanocontact. This approach does not allow one to explore propagating droplets, which can be particularly useful for the information transmission in applications utilizing droplets as information carriers.…”

Section: Introductionmentioning

confidence: 99%

Magnetic droplet solitons generated by pure spin currents

et al. 2017

View full text Add to dashboard Cite

Magnetic droplets are dynamical solitons that can be generated by locally suppressing the dynamical damping in magnetic films with perpendicular anisotropy. To date, droplets have been observed only in nanocontact spin-torque oscillators operated by spin-polarized electrical currents. Here, we experimentally demonstrate that magnetic droplets can be nucleated and sustained by pure spin currents in nanoconstriction-based spin Hall devices. Micromagnetic simulations support our interpretation of the data, and indicate that in addition to the stationary droplets, propagating solitons can be also generated in the studied system, which can be utilized for the information transmission in spintronic applications.

show abstract

“…Our most important physical result is the determination of the mean time it takes for a deterministically stable droplet to be ejected from the nanocontact due to thermal noise. Based on physical parameters from recent experiments [7,17], we estimate this time to be approximately 50 nanoseconds or a rate of droplet ejection of 20 MHz, which is within an order of magnitude of low-frequency observations from recent experiments. We estimate that this rate can be manipulated and, importantly, significantly decreased through appropriate choice of operating parameters.…”

Section: Introductionmentioning

confidence: 55%

Stochastic ejection of nanocontact droplet solitons via drift instability

Moore

Hoefer

2019

Phys. Rev. B

View full text Add to dashboard Cite

The magnetic droplet soliton is a large amplitude, coherently precessing wave state that exists in ferromagnetic thin films with perpendicular magnetic anisotropy. To effectively sustain a droplet, magnetic damping can be locally compensated in a nanocontact region that imparts spin-transfer torque; this has been successfully deployed in experiment to directly image the droplet and probe its dynamics electrically. However, theory predicts and experiments indicate the existence of a drift instability whereby the droplet is ejected from the spin-transfer-torque-active region and subsequently decays, an effect that may be enhanced or possibly induced by thermal fluctuations.Using soliton perturbation theory and large deviation theory, this work determines the soliton ejection rate and the most likely path an ejected soliton tracks in the presence of thermal fields.These results lead to an effective lower bound on the stability of magnetic droplet solitons in spintransfer torque nanocontact devices operating at finite temperature and point to ways in which droplets can be made more robust.

show abstract

Effect of Temperature on Magnetic Solitons Induced by Spin-Transfer Torque

Cited by 19 publications

References 34 publications

Generation and stability of dynamical skyrmions and droplet solitons

Generation and stability of dynamical skyrmions and droplet solitons

Magnetic droplet solitons generated by pure spin currents

Stochastic ejection of nanocontact droplet solitons via drift instability

Contact Info

Product

Resources

About