Magnetic properties of neodymium-small rare earth gallium garnets with the rare earth ions on two crystallographic sites

We measured the M-H hysteresis loops of n YBa 2 Cu 3 O x: Ag (n = 3, 5, and 7) and 3RBa 2 Cu 3 O x: Ag (R = Gd and Eu) as a function of temperature, and found that the residual magnetization and, hence, pinning is independent of n and the rare-earth ions (R and Y), but depends greatly on the processing conditions. These samples exhibit the strongest pinning force for high-temperature superconductors developed to date.

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THE SOL–GEL SYNTHESIS OF RARE-EARTH IONS SUBSTITUTED BARIUM HEXAFERRITES AND MAGNETIC PROPERTIES

Modern Physics Letters B ◽

10.1142/s0217984913501923 ◽

2013 ◽

Vol 27 (26) ◽

pp. 1350192 ◽

Cited By ~ 2

Author(s):

S. CAI ◽

P. H. XIN ◽

P. F. WANG ◽

B. B. ZHANG ◽

Y. B. HAN ◽

...

Keyword(s):

Magnetic Properties ◽

Rare Earth ◽

Magnetic Moments ◽

Sol Gel ◽

Barium Hexaferrite ◽

Anisotropy Field ◽

Average Diameter ◽

Rare Earth Ions ◽

Barium Hexaferrites ◽

The Rare Earth

In this paper, a series of rare-earth-doped barium hexaferrite powders ( Ba 0.95 Re 0.05- Fe 12 O 19 and Ba 0.95 Re 0.05 M 0.05 Fe 11.95 O 19: Re = La , Pr , Sm , Nd , Gd , Dy , Yb ; M = Zn 2+, Mn 2+, [Formula: see text]) were synthesized by the sol–gel self-combustion technology. The phase composition and the magnetic properties of the as-prepared barium hexaferrites were characterized and discussed with X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The results showed that the barium hexaferrites exhibited the magnetoplumbite phase structure with the average diameter of 45 nm. Magnetic properties study revealed that the variation of the saturation magnetization (Ms) was similar with the change of the rare-earth ions radius, but the change of Ms was low. This indicated that the magnetic moments of rare-earth ions could not affect Ms. The magnetocrystalline anisotropy field mainly influenced the anisotropism of hexaferrites, and the coercivity (Hc) of the rare-earth ions doped barium hexaferrites basically decreased with the increasing orbital quantum numbers (except Sm 3+ and Gd 3+). Further study showed the co-addition of Zn 2+ and Mn 2+ did not change the trend of Ms and Hc. Thus, it is concluded that the rare-earth ions played an important role for the anisotropy field of barium hexaferrites.

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Infrared and Electronic Spectra of Rare Earth Perovskites: Ortho-Chromites, -Manganites and -Ferrites

Applied Spectroscopy ◽

10.1366/000370270774371426 ◽

1970 ◽

Vol 24 (4) ◽

pp. 436-445 ◽

Cited By ~ 236

Author(s):

G. V. Subba Rao ◽

C. N. R. Rao ◽

J. R. Ferraro

Keyword(s):

Magnetic Properties ◽

Rare Earth ◽

Transition Metal ◽

Ir Spectra ◽

Electronic Spectra ◽

Transition Metal Ions ◽

Rare Earth Ions ◽

Electronic Transitions ◽

Rare Earth Ion ◽

The Rare Earth

The electronic and ir spectra of rare earth perovskites of the general formula LnZO3, where Ln is the rare earth ion or yttrium and Z is Cr, Mn, or Fe, have been studied in detail. The results have been discussed in terms of crystallography, magnetic properties, covalency of Ln—O and Z—O bonds, and Goodenough's one electron energy diagrams. In all these compounds the rare earth ions do not markedly affect the electronic transitions of the transition metal ions; the 3 d electrons clearly exhibit localized behavior. Both the electronic and ir spectra of the LnZO3 perovskites are comparable to the spectra of the corresponding transition metal sesquioxides, Z2O3.

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Structural, Morphological and Magnetic Characterization of Sm-substituted Ni-Zn Ferrite

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666181018093813 ◽

2020 ◽

Vol 10 (2) ◽

pp. 152-156 ◽

Cited By ~ 1

Author(s):

Muhammad Hanif bin Zahari ◽

Beh Hoe Guan ◽

Lee Kean Chuan ◽

Afiq Azri bin Zainudin

Keyword(s):

Magnetic Properties ◽

Rare Earth ◽

Saturation Magnetization ◽

Sol Gel ◽

Magnetic Behavior ◽

Rare Earth Ions ◽

Ion Concentration ◽

Zn Ferrite ◽

Auto Combustion ◽

Combustion Technique

Background: Rare earth materials are known for its salient electrical insulation properties with high values of electrical resistivity. It is expected that the substitution of rare earth ions into spinel ferrites could significantly alter its magnetic properties. In this work, the effect of the addition of Samarium ions on the structural, morphological and magnetic properties of Ni0.5Zn0.5SmxFe2-xO4 (x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) synthesized using sol-gel auto combustion technique was investigated. Methods: A series of Samarium-substituted Ni-Zn ferrite nanoparticles (Ni0.5Zn0.5SmxFe2-xO4 where x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) were synthesized by sol-gel auto-combustion technique. Structural, morphological and magnetic properties of the samples were examined through X-Ray Diffraction (XRD), Field-Emission Scanning Electron Microscope (FESEM) and Vibrating Sample Magnetometer (VSM) measurements. Results: XRD patterns revealed single-phased samples with spinel cubic structure up to x= 0.04. The average crystallite size of the samples varied in the range of 41.8 – 85.6 nm. The prepared samples exhibited agglomerated particles with larger grain size observed in Sm-substituted Ni-Zn ferrite as compared to the unsubstituted sample. The prepared samples exhibited typical soft magnetic behavior as evidenced by the small coercivity field. The magnetic saturation, Ms values decreased as the Sm3+ concentration increases. Conclusion: The substituted Ni-Zn ferrites form agglomerated particles inching towards more uniform microstructure with each increase in Sm3+ substitution. The saturation magnetization of substituted samples decreases with the increase of samarium ion concentration. The decrease in saturation magnetization can be explained based on weak super exchange interaction between A and B sites. The difference in magnetic properties between the samples despite the slight difference in Sm3+ concentrations suggests that the properties of the NiZnFe2O4 can be ‘tuned’, depending on the present need, through the substitution of Fe3+ with rare earth ions.

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