Spectrum erbium

Erbium produces a brilliant emerald-green thermoluminescence, as discussed in the previous Chapter. Like the mixed oxides containing holmium compared with H02O3, there is more fine-structure in the emission spectrum of Er20s than of the mixed oxides of erbium(III). A common feature is the sharp edge of... 

For our purposes, it is interesting to note that the perovskite ErAlo.9Cro.1O3 emits the continuous spectrum of Cr(III) without the red and green Er(III) bands in spite of the fact that the aqueous solution has e of erbium(III) at 5230 A equal to 3.2 to be compared with a-tenth of e, 1.3 of chromium(III) at 5750 A. The absorption spectrum of the nitrate solution is even more striking in a spectroscope, because the transitions of Er(III) are so much narrower. Quite generally, Cr(III) seems to be very effective to prevent narrow band luminescence of the lanthanides. 

Soret and Delafontaine identified holmium in 1878 by examination of its spectrum. The following year, Cleve separated its oxide from Marignac s erbia, a mixture of erbium, holmium and thulium oxides. He named this element Holmium, after his native town Holmia (Stockholm). The metal was produced in 1934 by Klemm and Bommer. 

Swedish physicist, astronomer, and spec-troscopist. He mapped the spectra of yttrium, erbium, didymium, lanthanum, scandium, thulium, and ytterbium, and in 1866 wrote a histoncal review of spectrum analysis. He also studied the magnetic properties of iron and iron ores. 

Spectrum of the Glowing Oxide.—Neodymium oxide is one of the very few solids with a discontinuous spectrum. The spectrum which was known long before neodymium was separated from its fellow element praesodymium, was briefly described by Bunsen1 in 1864, who in the same communication mentions the discovery by Bahr2 of the similarly banded spectrum of erbium oxide. Thus far, however, no thorough-going study seems to have been made of this class of spectrum. 

The characteristic 1540 nm emission of Er3"1" was observed via a silicon exciton-mediated energy transfer for Si Er3+ nanocrystals (12 nm) derived from an erbium amidinate precursor (Ji et al., 2004). Similarly, the PL spectrum of Er3"1" implanted Si nanocrystals showed two lines at 1535 and 1546 nm, having a much higher intensity when compared to Er3"1" implanted Si02 nanocrystals or Er implanted Si nanocrystals (Priolo et al., 2001). 

Four rare-earth elements (yttrium, ytterbium, erbium, and terbium) have been named in honor of this village. A year later, the Swedish chemist Lars Fredrik Nilson (1840-1899), discovered another element in "erbia" and he named it scandium (Sc) in honor of Scandinavia. At the same time, Nilson s compatriot, the geologist and chemist Per Theodor Cleve (1840-1905) succeeded in resolving the "erbia" earths yet another step further, when he separated it into three components erbium, "holmium" (Flo) and thulium (Tm). The name "holmium" refers to Stockholm (Qeve s native city) and had been independently discovered by the Swiss chemists Marc Dela-fontame (1838-1911) and Jacques-Louis Soret (1827-1890), who had coined the metal element X on the basis of its absorption spectrum. 

As was earlier reported, flexible properties of sol-gel technology may be used for modification of PLE spectra of the incorporated lanthanides. In particular, appearance of the strong band at PLE spectrum at 360 nm for the emission wavelength 1.54 pm was observed for the erbium-doped monolith xerogel silica-titania or titania/opal structure [3,4], However, in ftie case of excitation terbium in composite YAG/titania xerogel/opal the obtained PLE... 

Yttrium is one of the most abundant rare earth elements and its purification is easily accomplished. Yttrium fractions from a bromate series are freed from dysprosium, holmium, and erbium by fractional precipitation with ammonia, K2OO4, or NaNC>2. The latter is probably the most effective. Yttrium salts give no absorption lines ini the viable portion of the spectrum, consequently the removal of holmium and erbium is easily observed by the direct vision spectroscope. 

Particularly high spontaneous emission enhancements can be attained with emitters that have very narrow emission lines. Atomic transitions, e. g. in rare-earth elements have such narrow emission lines. For this reason, rare-earth doped cavities are a prime example of the emission enhancement provided by resonant cavities. The emission spectrum of an erbium-doped Si/Si02 resonant cav-... 

The temperature dependence of the magnetic field and quadrupole interaction in erbium metal have been followed between 4-2 and 40 K and analysed [142]. An estimate of —1-9(4) bam was suggested for the excited-state quadra-pole moment. In a more detailed study, the line intensities of the hyperfine spectrum in a single crystal of Er metal have been correlated with the magnetic structure previously determined by neutron diffraction methods [143]. 

Photoluminescence excitation (PLE) spectroscopy was carried out at 77K on oxidized porous silicon containing iron/erbium oxide clusters. The novel PLE spectrum of the 1535 nm Er PL band comprises a broad band extending from 350 to 570 nm and very week bands located at 640, 840, and 895 nm. The excitation at wavelengths of 400 - 560 nm was shown to be the most effective. No resonant PLE peaks related to the direct optical excitation of Er by absorption of pump photons were observed. The lack of the direct optical excitation indicates conclusively that Er is in the bound state and may be excited by the energy transfer within the clusters. 

PLE spectrum measured for 1.54 pm emission line in xerogel embedded in PAA (Fig. 4, curve a) reveals a set of the well-resolved excitation bands with the most intense band at 524 nm coinciding with the direct excitation of erbium through the 4Ii5/2 — 2Hn/2 transitions. 

In the NIR part of the spectrum, the best lanthanides are ytterbium, erbium and neodymium. Holmium has been less investigated, but shows an emission spectmm with a peak in the red and a peak in the IR. 

ADXD spectrum, 304/ electronic structure, 301 equations of stale, 305, 305/ 30 phase transition, 301 302 erbium... 

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