B. Rare earth ions in the iron garnet

2005 ◽  
pp. 326-327
Author(s):  
D. L. Huber
Keyword(s):  
Rare Earth ◽  
Rare Earth Ions ◽  
Iron Garnet

Faraday Rotation Spectra Analysis on TbYbBiIG Crystals in Optical Communication Band

2012 ◽  
Vol 562-564 ◽  
pp. 1753-1756
Author(s):  
Min Huang
Keyword(s):  
Rare Earth ◽  
Molecular Orbital ◽  
Faraday Rotation ◽  
Optical Communication ◽  
Octahedral Site ◽  
Rare Earth Ions ◽  
Spectra Analysis ◽  
Octahedral Sites ◽  
Iron Garnet

his paper is concerned with the FR spectra analysis on the Bi, Tb and Yb partially substituted iron garnet crystals of Tb3-x-yYbyBixFe5O12. A specific FR (-1617o/cm at 1.55μm), a low FWC (0.009%/nm at 25oC) of Tb0.91Yb1.38Bi0.71Fe5O12 crystals grown from Bi2O3 self-fluxed melts can be used as broadband optical communication components. In order to interpret their FR spectra, a theory based on molecular-orbital levels of Fe3+ in tetrahedral and octahedral sites is used. It is shown that in the case of higher Bi3+ substitution, FR is mainly determined by the contribution of Fe3+ in the octahedral site. Furthermore, two types of rare-earth ions (Tb3+ and Yb3+) moderate the contribution to FR from Fe3+ in octahedral and decahedral sites and eventually have caused that Bi-substituted mixed rare-earth iron garnet has a near-zero Faraday rotation wavelength coefficient (FWC).

scholarly journals Experimental Study of Electromagnetic-Assisted Rare-Earth Doped Yttrium Iron Garnet (YIG) Nanofluids on Wettability and Interfacial Tension Alteration

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3806 ◽  
Author(s):  
Zhen Yin Lau ◽  
Kean Chuan Lee ◽  
Hassan Soleimani ◽  
Hoe Guan Beh
Keyword(s):  
Magnetic Properties ◽  
Rare Earth ◽  
Interfacial Tension ◽  
Oil Recovery ◽  
Yttrium Iron Garnet ◽  
Rare Earth Ions ◽  
Yttrium Iron ◽  
Auto Combustion ◽  
Iron Garnet ◽  
Rare Earth Doped

Applications of nanoparticles (NPs) in the Enhanced oil recovery (EOR) method has become a major research field as nanoparticles are found to be able to interfere with the interfacial tension and wettability of multiphase fluids within the reservoir formation with or without the irradiance of the electromagnetic (EM) waves. For future EOR usage, a material with high temperature stability and low losses under oscillating wave is recommended, Yttrium Iron Garnet (YIG). This paper describes the synthesis of rare-earth doped YIG (RE-YIG, RE = (Lanthanum (La), Neodymium (Nd) and Samarium (Sm)) and the roles of rare-earth in alteration of magnetic properties. These magnetic properties are believed to have direct relation with the change in wettability, viscosity and interfacial tension of YIG nanofluids. Here we prepared the Y2.8R0.2Fe5O12 (R = La, Nd, Sm) NPs using the sol-gel auto-combustion technique and further annealed at 1000 °C for 3 h. The Field Emission Scanning Electron Microscope (FESEM) images reveal the particles having grain size ranging from 100–200 nm with high crystallinity and X-ray Powder Diffraction (XRD) shows varying shift of the peak position due to the bigger size of the rare-earth ions which resulted in structural distortion. The wettability of the nanofluid for all samples shows overall reduction under the influence of EM waves. On the other hand, the interfacial tension (IFT) and viscosity of RE-YIG nanofluids has lower value than the pure YIG nanofluids and decreases when the ionic radius of rare-earth decreases. Sm-YIG has the highest magnitude in IFT and magnetization saturation of 23.54 emu/g which suggests the increase in magnetization might contribute to higher surface tension of oil-nanofluid interface.

Characterization of Rare-Earth Fluoride Anti-Stokes Phosphors by Scanning arid Transmission Electron Microscopy

1971 ◽  
Vol 29 ◽  
pp. 142-143
Author(s):  
N. M. P. Low ◽  
L. E. Brosselard
Keyword(s):  
Electron Microscopy ◽  
Rare Earth ◽  
Elevated Temperatures ◽  
Stoichiometric Composition ◽  
Rare Earth Ions ◽  
Crystalline Solid ◽  
Precipitation Process ◽  
Rare Earth Fluoride ◽  
Earth Fluoride ◽  
Rare Earth Fluorides

There has been considerable interest over the past several years in materials capable of converting infrared radiation to visible light by means of sequential excitation in two or more steps. Several rare-earth trifluorides (LaF3, YF3, GdF3, and LuF3) containing a small amount of other trivalent rare-earth ions (Yb3+ and Er3+, or Ho3+, or Tm3+) have been found to exhibit such phenomenon. The methods of preparation of these rare-earth fluorides in the crystalline solid form generally involve a co-precipitation process and a subsequent solid state reaction at elevated temperatures. This investigation was undertaken to examine the morphological features of both the precipitated and the thermally treated fluoride powders by both transmission and scanning electron microscopy.Rare-earth oxides of stoichiometric composition were dissolved in nitric acid and the mixed rare-earth fluoride was then coprecipitated out as fine granules by the addition of excess hydrofluoric acid. The precipitated rare-earth fluorides were washed with water, separated from the aqueous solution, and oven-dried.

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

2020 ◽  
Vol 10 (2) ◽  
pp. 152-156 ◽  
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.

scholarly journals Structure, Luminescence, and Magnetic Properties of Crystalline Manganese Tungstate Doped with Rare Earth Ion

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3717
Author(s):  
Jae-Young Jung ◽  
Soung-Soo Yi ◽  
Dong-Hyun Hwang ◽  
Chang-Sik Son
Keyword(s):  
Magnetic Field ◽  
Rare Earth ◽  
Sintering Temperature ◽  
Luminescent Properties ◽  
Concentration Quenching ◽  
Rare Earth Ions ◽  
Precipitation Method ◽  
Rare Earth Ion ◽  
Co Precipitation ◽  
Quenching Phenomenon

The precursor prepared by co-precipitation method was sintered at various temperatures to synthesize crystalline manganese tungstate (MnWO4). Sintered MnWO4 showed the best crystallinity at a sintering temperature of 800 °C. Rare earth ion (Dysprosium; Dy3+) was added when preparing the precursor to enhance the magnetic and luminescent properties of crystalline MnWO4 based on these sintering temperature conditions. As the amount of rare earth ions was changed, the magnetic and luminescent characteristics were enhanced; however, after 0.1 mol.%, the luminescent characteristics decreased due to the concentration quenching phenomenon. In addition, a composite was prepared by mixing MnWO4 powder, with enhanced magnetism and luminescence properties due to the addition of dysprosium, with epoxy. To one of the two prepared composites a magnetic field was applied to induce alignment of the MnWO4 particles. Aligned particles showed stronger luminescence than the composite sample prepared with unsorted particles. As a result of this, it was suggested that it can be used as phosphor and a photosensitizer by utilizing the magnetic and luminescent properties of the synthesized MnWO4 powder with the addition of rare earth ions.

scholarly journals Selective Crystallization of Rare‐Earth Ions into Cationic Metal‐Organic Frameworks for Rare‐Earth Separation

2021 ◽  
Author(s):  
Huajun Yang ◽  
Fang Peng ◽  
Danielle E. Schier ◽  
Stipe A. Markotic ◽  
Xiang Zhao ◽  
...  
Keyword(s):  
Rare Earth ◽  
Metal Organic Frameworks ◽  
Rare Earth Ions ◽  
Selective Crystallization ◽  
Metal Organic
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