Structure and magnetic properties of FeNi/Ti sputtered multilayers

The microstructure, anisotropic magnetoresistance, magnetic properties and magnetic domain structure of sputtered FeNi films and [Ti/FeNi]n (n = 2-16) multilayers were comparatively analyzed. It was found that although the grain size increases with an increase of the FeNi thickness both in the case of FeNi films and [Ti/FeNi]n multilayers, it did not exceed 25 nm. The values of anisotropic magnetoresistance for FeNi films and [Ti/FeNi]n multilayers were close to each other showing a weak dependence on the total thickness of the multilayered structure. Coercivity for multilayers was found to be smaller than the coercivity of single layer FeNi films. Despite the absence of a direct exchange interaction between FeNi neighboring layers in the [Ti/FeNi]n structures, their domain structures were found to be quite different from magnetic domains in single layer films due to stray field compensation in the multilayers. Obtained results are useful for the development of sensitive elements for small magnetic field detectors and planar inductors. © 2013 Owned by the authors, published by EDP Sciences

Magnetization configurations in soft magnetic Fe-Nb-Cu-Si-B films with periodic nanoscale curvature

Barrier layers of porous alumina were used as substrates for depositing the Finemet alloy providing a flexible control over the curvature parameters. Investigation of macroscopic and local magnetization processes on samples with curvature diameter of 105 and 320 nm re-vealed the increased coercivity comparing to the flat films with similar magnetization reversal mechanism. The conditions for vortices formation were determined using micromagnetic modelling and verified experimentally.The reported study was funded by RFBR according to the research project mol_a № 18-32-00221

Исследование магнитных пленочных структур методом рентгеновской флуоресцентной спектроскопии

Программа развития УрФУ на 2013 год (п.1.2.2.3

Magnetization reversal in GdCo antidot films with perpendicular anisotropy

Influence of nanoscale antidot lattices on magnetization reversal processes in GdCo films with strong perpendicular anisotropy has been investigated. Lattice parameters have been set by choosing substrates prepared by anodizing aluminum foils in appropriate conditions. We have studied the influence of the nanoscale local curvature on magnetization processes by comparing flat antidot films, antidot films with curvature, and continuous films with curvature.This work was supported by the President of Russian Federation grant for young scientists (Contract 14.Y30.18.1891-MK)

HYSTERESIS PROPERTIES AND MAGNETIZATION REVERSAL IN FeMn/FM (FM=Co, Fe, Ni, FeNi) FILMS WITH EXCHANGE BIAS

Angular dependencies of hysteresis properties of various ferromagnetic layers exchange coupled to a pinning antiferromagnetic layer have been investigated experimentally. The re-sults have been interpreted and analyzed in detail using macrospin approximation and micro-magnetic simulation.This work was supported by the Russian Science Foundation (project No 19-72-00141)

Optical AR coatings of the Mid-IR band for ZnGeP2 single crystals based on ZnS and oxide aluminum

In this work, the parameters of antireflection interference coatings based on alternating layers of ZnS/Al2O3 on the laser-induced damage threshold (LIDT) of ZGP crystals under the action of Ho:YAG laser radiation at a wavelength of 2.097 μm were determined. The coating deposition was carried out using the ion-beam sputtering method. The LIDT of the sample with a coating based on alternating layers ZnS and Al2O3 was equal to WEo = 3.45 J/cm2, and the LIDT of the uncoated sample was equal to WEo = 2.23 J/cm2. An increase in the optical breakdown threshold by ~55% was observed after the deposition of an AR coating based on ZnS and Al2O3 materials. An assumption was made about the absence of local fluctuations in the composition and mechanical stresses in the case of the coated sample, namely that this leads to good adhesion of the multilayer coating to the polished surface of the crystal, and as a result to an increase in the optical breakdown threshold as compared to the uncoated sample due to closure of the dangling chemical bonds and bulk defects emerging on the polished surface

Micromagnetic modelling of stripe domains in thin films with a columnar microstructure

A micromagnetic model of thin films with columnar microstructure in the form of a matrix with reduced magnetic properties and embedded columns with high aspect ratio is presented. Such microstructure is typical for some films based on rare-earth and 3d transition metal alloys, in particular for La-Co films, that were chosen as an object for our modelling. Described structural features promote an effective perpendicular magnetic anisotropy that for thick enough films leads to formation of the stripe domain pattern. Our work addresses to the problem of finding equilibrium characteristics of stripe domains for the case of infinite columnar films. Herein it is shown how width of stripe domains, remanent magnetization and energies depend on number of replicas of periodic boundary conditions and the size of modelling volume. Equilibrium values of listed quantities can be found by extrapolating obtained dependencies. © 2021 Author(s).This work was supported by Russian Science Foundation, project No. 19-72-00141

Magnetic properties of soft magnetic cobalt-based alloy heat treated in presence of indium vapors

The effect of the indium presence on the magnetic properties of soft magnetic cobalt-based alloy during heat treatment (HT) was studied. It was shown that changes in magnetic characteristics were largely due to the impact mechanism of HT. The presence of indium vapors during HT increased the maximum magnetic permeability and changed magneto-optical hysteresis loops

Magnetic properties of Co-W thin films

In this paper, the magnetic properties and structure of the Co-W films of different compositions prepared by magnetron sputtering on glass substrates without and with Ta or Ru buffer layers were investigated. The dependences of coercive force on the W content for the studied films were non-monotonic. The peak value of the coercive force of about 400 Oe was observed for the films on glass and Ta layers with W content of 8-9 at. %. The films deposited on Ru layers had a coercive force of 4 times less, and it was practically independent of the W content in a wide range from 6 to 20 at. %. © Published under licence by IOP Publishing Ltd.Russian Science Foundation, RSF: 18-72-10044This work was carried out under the financial support by the RSF grant, project No. 18-72-10044