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Rare earth films

While discussing the role of the impurities in reactive metals, and continuing to use the R metals as typical examples, we have also to consider the effects due to the reactivity of the R and possible sources of contamination. As for the reactivity with hydrogen, the contamination of R thin films by RH2 is too important to be neglected. For instance, it is well-established that in thin rare earth films very often the... [Pg.557]

Fig. 3.7 Schematic representation of the rare earth film morphology as a function of nominal film thickness and annealing temperature... Fig. 3.7 Schematic representation of the rare earth film morphology as a function of nominal film thickness and annealing temperature...
The growth and microstmcture of switchable mirror thin fllrns involves specific aspects that need to be discussed before describing their physical properties. We focus first on Y, La and rare-earth films (for convenience all abbreviated as RE films), deposited in both their metallic and hydride forms. Some references to second-generation mirrors (Mg-RE) are included and third-generation switchable mirrors (Mg-TM) are shortly discussed separately. [Pg.277]

Chemical loading of rare-earth films by immersion in an aqueous KOH solution containing NaBH4 has been demonstrated by Van der Sluis [94] for Gd. The redox reaction forms BO2 and GdHs. The attractive feature of this technique is that, due to the high redox potential difference, it leads to almost stoichiometric trihydrides. The reaction is reversed by immersion in a 0.3 % H2O2 aqueous solution. [Pg.280]

Second-Generation Switchable Mirrors Magnesium-Rare Earth Films... [Pg.295]

Dynamic work function measurements showed a high reactivity of metallic rare earth film surfaces towards water vapor (Strasser et al. 1982). The initial fast work function decrease (fig. 10) indicates the rapid build-up of a surface dipole layer with the positive charge pointing away from the surface. This can be explained by a surface layer of OH groups. In contrast to the XPS results of Padalia et al. (1976) the work function curves show a similar behavior for Er and Yb. [Pg.258]

An understanding of strain effects in films is of critical importance for our subsequent discussion of superlattices in sect. 5. The topic of strain relief through interfacial accommodation began with Van der Merwe s treatment of critical thickness for the formation of interfacial dislocations (Van der Merwe 1950,1962) and has been the subject of reviews (Matthews 1979, Freund 1993). In the interest of brevity we present only a sketch of strain relief phenomena in what follows, and illustrate the substance of the discussion by relevant examples of magnetic behavior in thin rare-earth films. [Pg.26]

Poly crystalline rare earth films Homoge- 3.1.1. Y-Mg alloy 228... [Pg.83]

Polycrystalline rare earth films Homogeneous switching... [Pg.101]

Table 2. Magnetic Fundamentals of Rare-Earth Transition-Metal Thin Films... Table 2. Magnetic Fundamentals of Rare-Earth Transition-Metal Thin Films...
The same color variety is not typical with inorganic insertion/extraction materials blue is a common transmitted color. However, rare-earth diphthalocyanine complexes have been discussed, and these exhibit a wide variety of colors as a function of potential (73—75). Lutetium diphthalocyanine [12369-74-3] has been studied the most. It is an ion-insertion/extraction material that does not fit into any one of the groups herein but has been classed with the organics in reviews. Films of this complex, and also erbium diphthalocyanine [11060-87-0] have been prepared successfiiUy by vacuum sublimation and even embodied in soHd-state cells (76,77). [Pg.158]

Cerium/Rare Earth. Cerium 2-ethyIhexanoate [56797-01-4] and rare-earth driers promote polymerization and through dry. Like iron they are active at elevated temperature and, since they do not contribute to film discoloration, are recommended for white bake finishes and overprint varnishes where color is critical. Rare earths also find use at the other end of the temperature spectmm in coatings dried at low temperature and high humidity. [Pg.221]

Rare earth oxides and phosphors Ceramics (AI2O3) and glasses Mining ores and rocks Superconductors and precursor materials Thin films... [Pg.599]

Rare earth sulfides, selenides, and tellurides show semiconducting properties and have potential for application in thermoelectric generation. Thin film chalcogenides of various rare earths have been prepared by multisource evaporator systems [233]. [Pg.131]

Suryanarayanan R, Burn G (1976) A compact multi-source multi-substrate evaporator for thin film studies of rare earth sulphides. Thin Solid Films 35 263-271... [Pg.149]

Some elements, such as the rare earths and the refractory metals, have a high affinity for oxygen, so vaporization of these elements in a normal vacuum of about 10 4 Pa, would lead to the formation of at least a surface layer of oxide on a deposited film. The evaporation of these elements therefore requires the use of ultra-high vacuum techniques, which can produce a pressure of 10-9 Pa. [Pg.7]

Cyanine dyes are in principle capable of shifting the emission into the near-IR region [157], however, their ionic character makes it difficult to dope them into films by vacuum vapor evaporation. Other materials investigated for IR emission are complexes based on rare earth ions (Nd3+, Er3+), which are also used in inorganic amplifiers and lasers [158]. [Pg.131]

Gasgnier, M. (1995) The intricate world of rare erath thin films metals, alloys, intermetallics, chemical compounds. In Handbook on the Physics and Chemistry of Rare Earths, eds. Gschneidner. Jr., K.A. and Eyring, L. (Elsevier, Amsterdam, The Netherlands), Vol. 20, p. 105. [Pg.612]


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See also in sourсe #XX -- [ Pg.1259 ]




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