Structural, magnetic, and transport properties of Permalloy for spintronic experiments

Nahrwold, Gesche; Scholtyssek, Jan M.; Motl-Ziegler, Sandra; Albrecht, Ole; Merkt, U.; Meier, Guido

doi:10.1063/1.3431384

Cited by 67 publications

(39 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This result reinforces the importance of looking at the cross section of the nanostripe in order to do a rough comparison of different experimental results, even if the material properties are considered the same. In any case, the resistivity of the Py nanostripe can change significantly depending on the deposition method and conditions [25,26]. Therefore, a comparison at a glance between different experimental results can be very challenging.…”

Section: Discussionmentioning

confidence: 99%

Joule heating in ferromagnetic nanostripes with a notch

et al. 2015

View full text Add to dashboard Cite

The temperature in a ferromagnetic nanostripe with a notch subject to Joule heating has been studied in detail. We first performed an experimental real-time calibration of the temperature versus time as a 100 ns current pulse was injected into a Permalloy nanostripe. This calibration was repeated for different pulse amplitudes and stripe dimensions and the set of experimental curves were fitted with a computer simulation using the Fourier thermal conduction equation. The best fit of these experimental curves was obtained by including the temperature-dependent behavior of the electrical resistivity of the Permalloy and of the thermal conductivity of the substrate (SiO 2 ). Notably, a nonzero interface thermal resistance between the metallic nanostripe and the substrate was also necessary to fit the experimental curves. We found this parameter pivotal to understand our results and the results from previous works. The higher current density in the notch, together with the interface thermal resistance, allows a considerable increase of the temperature in the notch, creating a large horizontal thermal gradient. This gradient, together with the high temperature in the notch and the larger current density close to the edges of the notch, can be very influential in experiments studying the current assisted domain wall motion.

show abstract

Section: Discussionmentioning

confidence: 99%

Joule heating in ferromagnetic nanostripes with a notch

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The only parameter that is at this point arbitrary is the damping, here chosen to be λ = 0.1, which is not actually known for the case of Co monoatomic chains on Pt. In permalloy, for example, the damping is one order of magnitude smaller [46]. However, Pt is characterized by a much stronger spin-orbit coupling, which can enhance the damping (for example, FePt nanoparticles are reported to have a damping parameter as high as 0.76 [47]).…”

Section: For Co Chains On Ptmentioning

confidence: 99%

Thermally activated magnetization reversal in monatomic magnetic chains on surfaces studied by classical atomistic spin-dynamics simulations

Bauer

Mavropoulos

Lounis

et al. 2011

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

We analyze the spontaneous magnetization reversal of supported monoatomic chains of finite length due to thermal fluctuations via atomistic spin-dynamics simulations. Our approach is based on the integration of the Landau-Lifshitz equation of motion of a classical spin Hamiltonian at the presence of stochastic forces. The associated magnetization lifetime is found to obey an Arrhenius law with an activation barrier equal to the domain wall energy in the chain. For chains longer than one domain-wall width, the reversal is initiated by nucleation of a reversed magnetization domain primarily at the chain edge followed by a subsequent propagation of the domain wall to the other edge in a random-walk fashion. This results in a linear dependence of the lifetime on the chain length, if the magnetization correlation length is not exceeded. We studied chains of uniaxial and tri-axial anisotropy and found that a tri-axial anisotropy leads to a reduction of the magnetization lifetime due to a higher reversal attempt rate, even though the activation barrier is not changed.

show abstract

“…[ 22 ] 3. Spin-Structured Multilayers: Sequential Layer Switching and Crossed Magnetic Easy Axes Remarkably, this tuning procedure can be employed to fabricate not only single layers but also multilayered materials with precisely adjusted switching fi elds and arbitrarily aligned magnetic easy axes.…”

Section: Magnetic Anisotropy Control In Single Films Via Oblique Incimentioning

confidence: 99%

Spin‐Structured Multilayers: A New Class of Materials for Precision Spintronics

Schlage

Bocklage

Erb

et al. 2016

Adv Funct Materials

View full text Add to dashboard Cite

7423wileyonlinelibrary.com extensively explored to maximize the magnitude of the magnetoresistive signal, which is defi ned as the normalized difference of the electrical resistance in the antiparallel and parallel magnetic confi guration of the trilayer. The basic GMR and TMR characteristics of spintronic devices and thus their functionalities, however, did not signifi cantly change during the last decade. This is due to conventional magnetic multilayer design and its limitations based on the interplay of accessible magnetic anisotropy contributions. Here, we show that oblique incidence deposition (OID) can be used in an elegant way to achieve full control on the magnetic anisotropy in every individual layer of such magnetoresistive multilayer stacks for the fi rst time. The additional shape anisotropy component introduced via OID allows for arbitrarily crossed magnetic easy axes with adjustable switching fi elds and opens a path for customized spintronic devices with conceptually new functionalities.So far, two major approaches have been pursued to engineer fi eld-dependent relative magnetic confi gurations of two ferromagnetic layers. In the fi rst case, one of the ferromagnetic layers either exhibits an enhanced coercive fi eld or is magnetically pinned (exchange biased) by an additional antiferromagnetic layer of high magnetic anisotropy. Thus, only the magnetically uncoupled free layer follows small external fi elds, causing a change of the magnetic confi guration and the magnetoresistance. [ 13 ] In the second approach, an interlayer exchange coupling, the Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction, is used to align both layers relative to each other. [ 14 ] The interlayer coupling defi nes the magnetic saturation behavior and hence the functionality of the trilayer. In conventional systems, only parallel or antiparallel orientations of the ferromagnetic layers are reliably achieved. Effi cient RKKY coupling is observed for particular material combinations only and depends very sensitively on the interlayer thickness. [ 15,16 ] Therefore, conventional magnetic multilayer design is restricted to a limited number of magnetic confi gurations in the trilayers which constrains the design and control of magnetic spin structures that are available for realizing particular magnetoelectronic responses.Our approach enables one to realize and tune magnetic and magnetoresistive properties in spintronic multilayer systems that exceed the potential of conventional approaches by far. The technique is not based on exchange-bias or interlayer coupling and is not affected by their limitations. Every ferromagnetic layer of arbitrary chemical composition, as a constituent either Spin-Structured Multilayers: A New Class of Materials for Precision SpintronicsKai Schlage , * Lars Bocklage , Denise Erb , Jade Comfort , Hans-Christian Wille , and Ralf Röhlsberger * Magnetoelectronic multilayer devices are widely used in today's information and sensor technology. Their functionality, however, is limited by the inherent prop...

show abstract

Structural, magnetic, and transport properties of Permalloy for spintronic experiments

Cited by 67 publications

References 32 publications

Joule heating in ferromagnetic nanostripes with a notch

Joule heating in ferromagnetic nanostripes with a notch

Thermally activated magnetization reversal in monatomic magnetic chains on surfaces studied by classical atomistic spin-dynamics simulations

Spin‐Structured Multilayers: A New Class of Materials for Precision Spintronics

Contact Info

Product

Resources

About