scholarly journals Temperature Dependence of the Magnetic Properties of IrMn/CoFeB/Ru/CoFeB Exchange Biased Synthetic Antiferromagnets

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 387 ◽  
Author(s):  
Edoardo Albisetti ◽  
Giuseppe Scaramuzzi ◽  
Christian Rinaldi ◽  
Matteo Cantoni ◽  
Riccardo Bertacco ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Temperature Dependence ◽  
Data Storage ◽  
Exchange Bias ◽  
Magnetic Nanomaterials ◽  
Thermal Treatments ◽  
Saturation Field ◽  
Ferromagnetic Layers ◽  
Vibration Sample Magnetometry ◽  
Heating Up

Synthetic antiferromagnets (SAF) are widely used for a plethora of applications among which data storage, computing, and in the emerging field of magnonics. In this framework, controlling the magnetic properties of SAFs via localized thermal treatments represents a promising route for building novel magnonic materials. In this paper, we study via vibration sample magnetometry the temperature dependence of the magnetic properties of sputtered exchange bias SAFs grown via magnetron sputtering varying the ferromagnetic layers and spacer thickness. Interestingly, we observe a strong, reversible modulation of the exchange field, saturation field, and coupling strength upon heating up to 250 °C. These results suggest that exchange bias SAFs represent promising systems for developing novel artificial magnetic nanomaterials via localized thermal treatment.

The Formation of High-Coercivity, Oriented, Nanophase Cobalt Precipitates in Al2O3 Single Crystals by Ion Implantation

1999 ◽  
Vol 581 ◽  
Author(s):  
S. Honda ◽  
F. A. Modine ◽  
T. E. Haynes ◽  
A. Meldrum ◽  
J. D. Budai ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Ion Implantation ◽  
Single Crystals ◽  
Data Storage ◽  
Magnetic Circular Dichroism ◽  
Surface Region ◽  
Magnetic Data ◽  
High Coercivity ◽  
Saturation Field ◽  
Near Surface

ABSTRACTIon-implantation and thermal-processing methods have been used to form nanophase magnetic precipitates of metallic cobalt that are embedded in the near-surface region of single crystals of Al2O3. The Co precipitates are isolated, single-crystal particles that are crystallographically oriented with respect to the host Al2O3 lattice. Embedded nanophase Co precipitates were formed by the implantation of Co+ at an energy of 140 keV and a dose of 8 × 1016 ions/cm2 followed by annealing in a reducing atmosphere. The implanted/annealed Co depth profile, particle size distributions and shapes, and the orientational relationship between the nanophase precipitates and the host crystal lattice were determined using RBS/channeling, transmission electron microscopy, and x-ray diffraction. Magneto-optical effects arising from Co precipitates formed in the near-surface region of Al2O3 were observed and characterized using magnetic circular dichroism. Magnetic properties of the Co-particle/host nanocomposites were investigated in the temperature range of 77 to 295 K in applied fields of up to 10 kG using a superconducting quantum interference device (SQUID) magnetometer. Implantation of the Co particles by Pt or Xe ions produced a large anisotropic increase in their coercivity. Accordingly, these magnetic nanoparticle systems may be of interest for magnetic data storage applications. Details of the magnetic properties of the Co/Al2O3 nanocomposites including their retentivity, coercivity, saturation field, and magnetic anisotropy are presented.

Effect of Thickness on Mechanically Tunable Magnetic Anisotropy of FeGa Thin Films Deposited on Flexible Substrates

2015 ◽  
Vol 815 ◽  
pp. 227-232 ◽  
Author(s):  
Ying Yu ◽  
Shu Hong Xie ◽  
Qing Feng Zhan
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Magnetic Anisotropy ◽  
Effective Strain ◽  
Anisotropy Field ◽  
Saturation Field ◽  
Effective Anisotropy ◽  
Magnetostriction Constant ◽  
The Difference ◽  
Different Strains

A practical way to manipulate the magnetic anisotropy of magnetostrictive FeGa thin films grown on flexible polyethylene terephthalate (PET) substrates is introduced in this study. The effect of film thickness on magnetic properties and magnetostriction constant of polycrystalline FeGa thin films was investigated. The anisotropy field Hk of flexible FeGa films, i.e., the saturation field determined by fitting the hysteresis curves measured along the hard axis, was enhanced with increasing the tensile strain applied along the easy axis of the thin films, but this enhancement via strain became unconspicuous with increasing the thickness of FeGa films. In order to study the magnetic sensitivity of thin films responding to the external stress, we applied different strains on these films and measure the corresponding anisotropy field. Moreover, the effective magnetostriction constant of FeGa films was calculated from the changes of both anisotropy field and external strain based on the Villari effect. A Neel’s phenomenological model was developed to illustrate that the effective anisotropy field of FeGa thin films was contributed from both the constant volume term and the inverse thickness dependent surface term. Therefore, the magnetic properties for the volume and surface of FeGa thin films were different, which has been verified in this work by using vibrating sample magnetometer (VSM) and magneto-optic Kerr effect (MOKE) system. The anisotropy field contributed by the surface of FeGa film and obtained by MOKE is smaller than that contributed by the film volume and measured by VSM. We ascribed the difference in Hk to the relaxation of the effective strain applied on the films with increasing the thickness of films.

Effects of Ta2O5 addition on the microstructure and temperature dependence of magnetic properties of MnZn ferrites

2009 ◽  
Vol 321 (5) ◽  
pp. 438-441 ◽  
Author(s):  
Lezhong Li ◽  
Zhongwen Lan ◽  
Zhong Yu ◽  
Ke Sun ◽  
Ming Luo ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Temperature Dependence ◽  
Mnzn Ferrites

Temperature dependence of the magnetic properties of mono-dispersed Co0.5Zn0.5Fe2O4 microtubes derived from different templates

2018 ◽  
Vol 30 (3) ◽  
pp. 2809-2820
Author(s):  
Peng-zhao Gao ◽  
Zhi-bo Huang ◽  
Hang-bo Zheng ◽  
Xiao-pan Liu ◽  
Jin Wen ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Temperature Dependence

scholarly journals Impact of ZrO2 Additive on Microstructure, Magnetic Properties, and Temperature Dependence of the Initial Permeability of LiTiZn Ferrite Ceramics

2021 ◽  
Author(s):  
Andrey Malyshev ◽  
Anna B. Petrova ◽  
Anatoly P. Surzhikov
Keyword(s):  
Magnetic Properties ◽  
Temperature Dependence ◽  
Defect Structure ◽  
Initial Permeability ◽  
Experimental Temperature ◽  
Mathematical Treatment ◽  
Experimental Temperature Dependence ◽  
Average Grain Size ◽  
Soft Ferrite ◽  
Microstructure And Magnetic Properties

Abstract The effect of the diamagnetic ZrO2 addition on the microstructure and magnetic properties of LiTiZn ferrite ceramics, including the shape and parameters of the temperature dependence of the initial permeability, has been investigated. The defect structure of ferrite ceramic samples is assessed according to our earlier proposed method based on mathematical treatment of the experimental temperature dependencies of the initial permeability. The method is recommended for defects monitoring of soft ferrite ceramics and ferrite products. It was found that the defect structure of ferrite ceramics increased by 350% with an increase in the concentration of the ZrO2 additive in the range of (0–0.5) wt.%. In this case, for the same samples, the increase in the true physical broadening of reflections is only 20%, and the coercive force by 50%. Simultaneously, the maximum of the experimental temperature dependence of the initial permeability dropped by 45%. The microstructure of all samples is characterized with a similar average grain size according to the SEM data. However, samples with the 0.5wt.% of ZrO2 are characterized by the formation of conglomerates. A linear relationship was obtained between the defect structure and the width of the reflections, which indicates that this parameter is related to the elastic stress of ferrite ceramics.

scholarly journals FMR Study of Temperature Dependence of Magnetic Properties of Nanocrystalline 0.90(Fe2O3)/0.10ZnO

2011 ◽  
Vol 120 (6) ◽  
pp. 1070-1073 ◽  
Author(s):  
N. Guskos ◽  
S. Glenis ◽  
G. Zolnierkiewicz ◽  
J. Typek ◽  
D. Sibera ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Temperature Dependence
Sign in / Sign up

Export Citation Format

Share Document