Exchange bias and magnetic anisotropies in Co nanowire/IrMn film heterostructures

Verbeno, C.H.; Paes, Vagner Zeizer Carvalho; Krohling, A.C.; Bueno, T.E.P.; Geshev, J.; Lierop, J. van; Passamani, E. C.

doi:10.1016/j.jmmm.2021.168768

Cited by 3 publications

(1 citation statement)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the downside, as a result of the size reduction of the AFM nanomaterials, finite size effects have been observed in AFM nanoparticles, yielding to the appearance of a blocking temperature, T B , that suppresses the EB effect well below T N [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 ]. Furthermore, the production and study of well-defined and homogeneous core (FM)/shell (AFM) nanowires is still demanded [ 13 , 28 , 29 , 30 , 31 ]. It should be noted that other types of materials where Ni is also in the Ni 2+ oxidation state can show interesting magnetic phenomena at the nanoscale.…”

Section: Introductionmentioning

confidence: 99%

Exchange Bias Effect of Ni@(NiO,Ni(OH)2) Core/Shell Nanowires Synthesized by Electrochemical Deposition in Nanoporous Alumina Membranes

Fernández

Gutiérrez

González

et al. 2023

IJMS

View full text Add to dashboard Cite

Tuning and controlling the magnetic properties of nanomaterials is crucial to implement new and reliable technologies based on magnetic hyperthermia, spintronics, or sensors, among others. Despite variations in the alloy composition as well as the realization of several post material fabrication treatments, magnetic heterostructures as ferromagnetic/antiferromagnetic coupled layers have been widely used to modify or generate unidirectional magnetic anisotropies. In this work, a pure electrochemical approach has been used to fabricate core (FM)/shell (AFM) Ni@(NiO,Ni(OH)2) nanowire arrays, avoiding thermal oxidation procedures incompatible with integrative semiconductor technologies. Besides the morphology and compositional characterization of these core/shell nanowires, their peculiar magnetic properties have been studied by temperature dependent (isothermal) hysteresis loops, thermomagnetic curves and FORC analysis, revealing the existence of two different effects derived from Ni nanowires’ surface oxidation over the magnetic performance of the array. First of all, a magnetic hardening of the nanowires along the parallel direction of the applied magnetic field with respect their long axis (easy magnetization axis) has been found. The increase in coercivity, as an effect of surface oxidation, has been observed to be around 17% (43%) at 300 K (50 K). On the other hand, an increasing exchange bias effect on decreasing temperature has been encountered when field cooling (3T) the oxidized Ni@(NiO,Ni(OH)2) nanowires below 100 K along their parallel lengths.

show abstract

Section: Introductionmentioning

confidence: 99%

Exchange Bias Effect of Ni@(NiO,Ni(OH)2) Core/Shell Nanowires Synthesized by Electrochemical Deposition in Nanoporous Alumina Membranes

Fernández

Gutiérrez

González

et al. 2023

IJMS

View full text Add to dashboard Cite

show abstract

Magnetic coercivity control via buffer layer roughness in Pt/Co multilayers

Verbeno

Zázvorka

Nowak

et al. 2023

Journal of Magnetism and Magnetic Materials

View full text Add to dashboard Cite

Formation of helical spin alignment in the AFM/FM/AFM trilayers by spin–orbit torque controlled exchange bias

Choi,

Yoon,

Kim

et al. 2023

APL Materials

View full text Add to dashboard Cite

Non-collinear spin structures can exhibit unusual magnetic properties that cannot be expected in an ordinary collinear ferromagnet (FM) due to the chiral alignment of magnetic moments, offering new opportunities for applications in the field of spintronics. In the present study, we demonstrate that exchange bias pinning can be applied to a single FM layer in two different directions simultaneously, resulting in modified magnetic behaviors due to the formation of non-collinear helical spin structures in the multilayers of Co0.7Ni0.3O (antiferromagnet, AFM)/Co0.7Ni0.3 (FM)/Co0.7Ni0.3O (AFM)/Pt (heavy metal, HM). The pinning of spins at one interface between FM and AFM/HM was controlled by spin Hall current originating from the electrical current through the HM layer at room temperature, while the spins at the other interface between FM and AFM were pinned in a fixed direction, hence allowing for the formation of a helical spin structure along the FM layer thickness with controllable chirality at room temperature. Modified magnetic behaviors of a helical spin structure were confirmed from measurements of magnetic hysteresis and magnetoresistance, as well as direct observation of magnetic domains.

show abstract

Exchange bias and magnetic anisotropies in Co nanowire/IrMn film heterostructures

Cited by 3 publications

References 29 publications

Exchange Bias Effect of Ni@(NiO,Ni(OH)2) Core/Shell Nanowires Synthesized by Electrochemical Deposition in Nanoporous Alumina Membranes

Exchange Bias Effect of Ni@(NiO,Ni(OH)2) Core/Shell Nanowires Synthesized by Electrochemical Deposition in Nanoporous Alumina Membranes

Magnetic coercivity control via buffer layer roughness in Pt/Co multilayers

Formation of helical spin alignment in the AFM/FM/AFM trilayers by spin–orbit torque controlled exchange bias

Contact Info

Product

Resources

About