Lattice Location and Luminescence Behavior of Rare Earth Elements Implanted in GaN

AbstractSingle crystalline GaN-layers were implanted with radioactive 167Tm and 169yb ions, and their lattice sites were determined using the emission channeling technique. After the decay of 167Tm to 167Er, photoluminescence studies were performed. Upon room temperature implantation, rare earth atoms immediately occupy relaxed substitutional sites with an average relaxation of about 0.025 nm. Isochronal annealing treatments up to 800 °C and co-implantation of oxygen to a dose an order of magnitude greater than that of the Tm or Yb do not influence the rare earth lattice sites. A variety of different rare earth related luminescence lines are observed, and co-implantation of oxygen strongly changes the line intensities.

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Distribution of rare-earth elements in rock-forming minerals of corundum-bearing rocks of the Khitoostrov deposit (North Karelia)

Vestnik of Saint Petersburg University Earth Sciences ◽

10.21638/spbu07.2021.403 ◽

2021 ◽

Vol 66 (4) ◽

Author(s):

Ekaterina Yu. Akimova ◽

◽

Sergey G. Skublov ◽

◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Isotopic Composition ◽

Mobile Belt ◽

Positive Slope ◽

Rock Formation ◽

Ree Distribution ◽

Lree Enrichment ◽

Order Of Magnitude ◽

The Difference

The distribution of rare-earth elements (SIMS method) in minerals from the rocks of the Khitoostrov occurrence (Belomorian mobile belt of Eastern Fennoscandia) was studied: corundum-bearing metasomatites with anomalous isotopically light oxygen and hydrogen and garnet amphibolites after gabbro with normal isotopic composition. The study was accompanied by estimates of P-T parameters of rock formation using multi-equilibrium thermobarometry (TWEEQU method). Temperatures calculated for garnet amphibolites after gabbro fall within the range of 730–770 ° C, pressures - 13–14 kbar; for corundum-bearing rocks, temperatures were 680–710 ° C, pressures - 6.5–7.5 kbar. Corundum-bearing rocks were formed at slightly lower temperatures and at significantly lower pressures than garnet amphibolites after gabbro. The REE distribution spectra in garnets from apogabbroic amphibolites are characterized by a clearly pronounced slope from light to heavy REE, while in garnets from corundum-bearing rocks they have a less pronounced positive slope, which is associated with a noticeable enrichment of garnets in LREE and an insignificant depletion of HREE. Calcium amphiboles from corundum-bearing rocks are significantly enriched in rare-earth elements as compared to amphiboles from garnet amphibolites after gabbro, especially LREE (by more than an order of magnitude) and, to a lesser extent, MREE. Plagioclases from corundum-bearing rocks are also enriched in LREE against the background of garnet amphibolites. Thus, in all the studied minerals of corundum-bearing rocks LREE enrichment is recorded. It isn’t manifested in the minerals of amphibolites and, obviously, isn’t related to the difference in P-T parameters of rock formation. Consequently, LREE was transferred by a specific fluid during mineral-forming processes, which led to the formation of metasomatites with an anomalous isotopic composition of oxygen and hydrogen.

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Lattice Location and Cathodoluminescence Studies of Ytterbium/Thulium Implanted 2H-Aluminium Nitride

MRS Proceedings ◽

10.1557/proc-743-l6.16 ◽

2002 ◽

Vol 743 ◽

Cited By ~ 7

Author(s):

U. Vetter ◽

M. F. Reid ◽

H. Hofsäss ◽

C. Ronning ◽

J. Zenneck ◽

...

Keyword(s):

Room Temperature ◽

Lattice Site ◽

Electron Transition ◽

Lattice Location ◽

Temperature Dependent ◽

Time Resolved ◽

Annealing Temperatures ◽

Visible Luminescence ◽

On Line ◽

Emission Channeling

ABSTRACTLattice location studies of radioactive 169Yb ions, implanted at an energy of 60 keV into 2H-AlN at the on-line isotope separator ISOLDE at CERN, were performed using the emission channeling technique. The measurements, which yield a substitutional Al lattice site for the implanted ions, were recorded for annealing temperatures ranging from 293 K to 1273 K. After complete decay of 169Yb to 169Tm cathodoluminescence measurements were performed in the range 12 K – 300 K. The samples show a strong visible luminescence at 460 - 470 nm at room temperature, which is attributed to the 1D2−3F4 intra-4f electron transition of Tm3+. At 12 K the luminescence is dominated by transitions starting from the 1H6 multiplet. Time resolved as well as temperature dependent cathodoluminescence measurements are presented and discussed.The lattice location as well as the time resolved cathodoluminescence measurements suggest that there is only one pronounced site of the implanted ions in the AlN lattice and that this is the substitutional aluminium site.

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Formation and Stabilities of Free Bilirubin and Bilirubin Complexes with Transition and Rare-Earth Elements

Clinical Chemistry ◽

10.1093/clinchem/17.12.1165 ◽

1971 ◽

Vol 17 (12) ◽

pp. 1165-1170 ◽

Cited By ~ 28

Author(s):

Rance A Velapoldi ◽

Oscar Menis

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Lanthanide Complexes ◽

Room Temperature ◽

Covalent Bonding ◽

Experimental Conditions ◽

Square Planar ◽

Square Planar Complexes ◽

The Stability ◽

Complex Stabilities

Abstract We investigated complexes formed between bilirubin and transition or rare-earth elements, and their relative stabilities. Relative rates of complex formation were analogous to metalloporphyrin and metal complex stabilities, according to the Irving—Williams series. Transition metals that formed strong, square planar complexes caused rapid bilirubin degradation. Iron(II) was oxidized to iron(III) in the bilirubin complex. Of the lanthanide complexes, only samarium(III) showed covalent bonding tendencies. Comparative molar absorptivities were calculated for several of the metal— bilirubin complexes. The stability of bilirubin in several solvents and under various experimental conditions is reported. At room temperature, bilirubin photooxidizes to biliverdin on exposure to laboratory light.

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OPTICAL DOPING OF NITRIDES BY ION IMPLANTATION

Modern Physics Letters B ◽

10.1142/s0217984901003172 ◽

2001 ◽

Vol 15 (28n29) ◽

pp. 1281-1287 ◽

Cited By ~ 26

Author(s):

E. ALVES ◽

K. LORENZ ◽

R. VIANDEN ◽

C. BOEMARE ◽

M. J. SOARES ◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Room Temperature ◽

Lattice Site ◽

Rutherford Backscattering Spectrometry ◽

Complete Recovery ◽

Nitrogen Atmosphere ◽

Site Location ◽

Damage Behavior ◽

Recombination Processes

A series of rare earth elements (RE) were implanted in GaN epilayers to study the lattice site location and optical activity. Rutherford backscattering spectrometry in the channeling mode (RBS/C) was used to follow the damage behavior in the Ga sublattice and the site location of the RE. For all the implanted elements (Ce, Pr, Dy, Er, and Lu) the results indicate the complete substitutionality on Ga sites after rapid thermal annealing at 1000°C for 2 min. The only exception occurs for Eu, which occupies a Ga displaced site. Annealing at 1200°C in nitrogen atmosphere at a pressure of 1GPa is necessary to achieve the complete recovery of the damage in the samples. After annealing the recombination processes of the implanted samples were studied by above and below band gap excitation. For Er implanted samples besides the 1.54 μm emission green and red emissions are also observed. Red emissions from 5 D 0 → 7 F 2 and 3 P 0 → 3 F 2 transitions were found in Eu and Pr implanted samples even at room temperature.

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Electro-optic properties of singly and doubly doped lithium niobate crystal by rare earth elements for optoelectronic and laser applications

The European Physical Journal Applied Physics ◽

10.1051/epjap/2019180317 ◽

2019 ◽

Vol 85 (3) ◽

pp. 30502 ◽

Cited By ~ 3

Author(s):

Nune Mkhitaryan ◽

Jean Zaraket ◽

Ninel Kokanyan ◽

Edvard Kokanyan ◽

Michel Aillerie

Keyword(s):

Rare Earth ◽

Lithium Niobate ◽

Rare Earth Elements ◽

Figure Of Merit ◽

Room Temperature ◽

Laser Applications ◽

Geometric Configurations ◽

Electro Optic ◽

Direct Technique ◽

Nonlinear Devices

Congruent lithium niobate (LN) doped with rare-earth elements is a promising host for integrated optic combining the properties straightforwardly associated to the dopant with the good electro-optic (EO) properties. By direct technique based on interferometric optical arrangement at a wavelength of 633 nm and at room temperature, we have experimentally determined the figure of merit F = n3reff, (n is the refractive index and reff, the effective EO coefficient) and finally calculated the EO coefficients reff of the third-column of the unclamped EO tensor of three series of singly doped LN with Yb3+, Ho3+, Tm3+ and two series of doubly doped Er3+–Yb3+. It is found that in all the studied opto-geometric configurations, the unclamped figure of merit and consequently the corresponding EO coefficients are relatively constant in the considered dopant concentration range. As the figure of merit, F qualifies crystals for EO modulation and laser applications, all reported results confirm that the LN singly or doubly doped with rare-earth elements are very promising versatile candidates for several multifunctional nonlinear devices in optoelectronic and laser applications.

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Room temperature photoluminescence of (RE)NiO3 (RE=La, Y, Er, Ho, Nd and La1-xYx)

Cerâmica ◽

10.1590/s0366-69132007000200009 ◽

2007 ◽

Vol 53 (326) ◽

pp. 165-168

Author(s):

Z. R. Silva ◽

D. M. A. Melo ◽

A. C. Lima ◽

E. Longo ◽

M. A. F. Melo ◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Room Temperature ◽

Emission Spectra ◽

Polymeric Precursor ◽

Room Temperature Photoluminescence ◽

Structural Order ◽

Visible Photoluminescence ◽

Band Emission

The nature of visible photoluminescence (PL) at room temperature in amorphous (RE)NiO3 (RE=La, Y, Er, Ho, Nd and La1-xYx) is discussed. Powders of this system were prepared by the polymeric precursor technique. The presence of broad PL band emission spectra at room temperature indicated increasing structural order with addition of rare earth elements.

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Ecological/economical Assessment of Pit Waters (the Ural Copper Pyrite Watersealed Mines as a Study Case)

Water sector of Russia: problems, technologies, management - Методы оценки и механизмы регулирования водопользования в современных условиях ◽

10.35567/1999-4508-2016-1-5 ◽

2016 ◽

pp. 52

Author(s):

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Water Discharge ◽

Water Bodies ◽

Raw Material ◽

Environmental Damage ◽

Ferrous Metals ◽

Order Of Magnitude ◽

Copper Pyrite ◽

Non Ferrous Metals

Worked-out copper pyrite mines are one of the considerable sources of hydrosphere pollution. Analysis of components of the environmental damage to surface water bodies due to treated pit water discharge has been carried out. Environmental damage to water bodies caused by the Levikha and Degtyarsk mines pit water discharge both during the mines operation and after watersealing of them is assessed in 100–200 million rubles per year? And the value of the prevented environmental damage is one order of magnitude higher. Individual components contribution to environmental damage has been determined: during the mines operation cooper was the main pollutant, after the pumping termination zinc became the main pollutant. It has been stated that pit water is a reliable renewable source of non-ferrous metals and rare earth elements and can be considered a hydro/mineral raw material deposit. Commercial content of non-ferrous metals and rare earth elements in the watersealed copper pyrite mines has been estimated. Total recoverable value of non-ferrous metals and rare earth elements in the Levikha mine pit water exceeds 4 million US dollars per year. Rare earth elements comprise the main share. It has been shown that potential recoverable value of the components exceeds cost of annual neutralization of acidic pit water and the value of environmental damage caused by the treated pit water discharge.

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Rare earth elements (REE) in freshwater, marine, and terrestrial ecosystems in the eastern Canadian Arctic

10.1101/174870 ◽

2017 ◽

Author(s):

Gwyneth Anne MacMillan ◽

John Chételat ◽

Joel Heath ◽

Raymond Mickpegak ◽

Marc Amyot

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Canadian Arctic ◽

Terrestrial Ecosystems ◽

Trophic Levels ◽

Carbon And Nitrogen ◽

Northern Regions ◽

Order Of Magnitude ◽

Mining Projects ◽

Eastern Canadian Arctic

ABSTRACTFew ecotoxicological studies exist for rare earth elements (REEs), particularly field-based studies on their bioaccumulation and food web dynamics. REE mining has led to significant environment impacts in several countries (China, Brazil, U.S.), yet little is known about the fate and transport of these contaminants of emerging concern. To understand how REEs behave in pristine northern food webs, we measured REE concentrations and carbon and nitrogen stable isotope ratios (∂15N, ∂13C) in biota from marine, freshwater, and terrestrial ecosystems of the eastern Canadian Arctic (N=339). Northern ecosystems are potentially vulnerable to REE enrichment from prospective mining projects at high latitudes. Wildlife harvesting and tissue sampling was partly conducted by local hunters through a community-based monitoring project. Results show that REE generally follow a coherent bioaccumulation pattern for sample tissues, with some anomalies for redox-sensitive elements (Ce, Eu). Highest REE concentrations were found at low trophic levels, especially in vegetation and aquatic invertebrates. Terrestrial herbivores, ringed seal, and fish had low REE levels in muscle tissue (<0.1 nmolg-1), yet accumulation was an order of magnitude higher in all liver tissues. Age- and length-dependent REE accumulation also suggest that REE uptake is faster than elimination for some species. Overall, REE bioaccumulation patterns appear to be species- and tissue-species, with limited potential for biomagnification. This study provides novel ecotoxicological data on the behaviour of REE in ecosystems and will be useful for environmental impact assessment of REE enrichment in northern regions.

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The distribution pattern of Rare Earth Elements (REE) in Vitis vinifera L. discriminates the substrate of growth ?

10.5194/egusphere-egu2020-5770 ◽

2020 ◽

Author(s):

Marcella Barbera ◽

Pierpaolo Zuddas ◽

Filippo Saiano

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Vitis Vinifera ◽

Distribution Pattern ◽

Vitis Vinifera L ◽

Experimental Conditions ◽

Plant Parts ◽

Aerial Parts ◽

Order Of Magnitude ◽

Leaves And Roots

Rare Earth Elements (REE) have been employed to stimulate the plant growth in national and international strategies while their role still remains controversial as the process involved in soil-plant system is not completely understood yet. &#160;In this study we have investigated the effect of REE amount in the substrate during the Vitis vinifera L growth analysing the REE distribution in the different part of the plants. Experiments were carried out over 1 year using two different substrates: one with a "natural" substrate (blank experiments) and another using the same substrate artificially enriched by an equimolar solution of REE (spiked experiments).We found that both plant mass and amount of REE in leaves are both not influenced by the substrate enrichment. However, roots are by 1 order of magnitude enriched in REE for the 3 orders of magnitude enriched substrate of growth. This indicates that Vitis vinifera L. does not significantly transfer REE into the aerial parts during growth while identify roots as the plant critical parts responsible for the filtering of the environmental stress.&#160; Plotting the REE normalized distribution for every element, the different experimental conditions can be significantly discriminated: under spiked substrate conditions, REE normalised distribution shows a &#8216;zig zag&#8217; pattern in both leaves and roots. We propose that the REE normalised distribution pattern measured in the different plant parts (leaves and roots) can be used to discriminates the conditions of substrate characteristics during the vitis vinifera growth. Acting as natural tracers, the REE normalised distribution could be potentially used as tool tracing the substrate origin of the Vitis vinifera plant.&#160;

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