Quantum nano-photonic devices based on rare-earth ions (Conference Presentation)

2018 ◽  
Author(s):  
Andrei Faraon
Keyword(s):  
Rare Earth ◽  
Photonic Devices ◽  
Rare Earth Ions

scholarly journals Modified absorption attributes of neodymium doped magnesium-zinc-sulfophosphate glass

2017 ◽  
Vol 13 (3) ◽  
Author(s):  
Nur Nabihah Yusof ◽  
Sib Krishna Ghoshal ◽  
Muhammad Firdaus Omar
Keyword(s):  
Rare Earth ◽  
Glass Network ◽  
Xrd Analysis ◽  
Photonic Devices ◽  
Rare Earth Ions ◽  
Glass System ◽  
Ion Concentration ◽  
Subsequent Transformation ◽  
Physical Density ◽  
Doped Glass

Rare-earth doped glass systems with improved absorption and emission features are greatly demanding for diverse applications. In this endavour, selection of right glass host, modifier, rare earth ions with optimized composition is the key issue. This communication reports the conventional melt-quench synthesis of neodymium (Nd3+) doped magnesium-zinc- sulfophosphate glass system of the form (60-x)P2O5-20MgO-20ZnSO4-xNd2O3 (x = 0, 0.5, 1, 1.5, 2.0 and 2.5 mol%). The influence of varying Nd3+ contents on the physical (density, molar volume, molar refractivity, refractive index and electronic polarizability) and absorption properties of the prepared glass system is determined. The amorphousity of the obtained samples is confirmed by XRD analysis. The glass refractive indices (ranged from 1.85 to 1.90)  and densites (between 2.63 to 2.77 g.cm-3) are found to increase with increasing concentration of Nd3+ ion. Furthermore, the energies associated with the direct and indirect optical transitions across the forbidden gap are observed to reduce with the increase of Nd3+ ion concentration. Meanwhile, the increase of Urbach energy with increasing Nd3+doping is ascribed to the interaction of rare earth ions with the ligands of the glass network and subsequent transformation of weak bonds into defects. The room temperature UV–Vis-NIR spectra revealed eleven absorption band corresponding to the transitions from the ground state to various excited states of the Nd3+ ion. Incorporation of  Nd3+ ion is discerned to enhance the glass absorbance appreciably together with the alteration of physical properties. Present findings may be beneficial for the advancement of Nd3+ ions doped magnesium-zinc-sulfophosphate glass system based photonic devices especially for infrared solid state laser.

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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