M. E. Voronchikhina, A. V. Matasov, V. Yu. Ivanov, . D. Iskhakova, A. M. Kuzmenko, M. A. Sysoev, A. A. Mukhin
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引用次数: 0
Abstract
(La1–xRx)3Ga5SiO14 single crystals and ceramic solid solutions where R = Gd–Ho and 0 ≤ х ≤ 0.4 (as-batch) were characterized by X-ray powder diffraction (XRD) and analytical electron microscopy in order to determine the solubility limits of lanthanides in the langasite structure. Langasite-based solid solutions are the dominant phase up to the highest concentrations, but at x ≥ 0.15 for holmium and x ≥ 0.2 for terbium, garnet R3Ga5O12 and La2SiO5-type impurity phases start to precipitate. Langasite single crystals have homogeneous structure where Tb, Dy, or Ho substitutes for La up to х = 0.05, and where Gd does up to х = 0.2. At х > 0.1, however, inclusions of impurity phases with the above structures appear in (La1–xTbx)3Ga5SiO14 crystals. The magnetization curves of (La1–xRx)3Ga5SiO14 (R = Ho and Tb) crystals measured at 1.85–2 K exhibit strong magnetocrystalline anisotropy, where the magnetic moment per R3+ ion is roughly the same for all of the heavy lanthanide concentrations studied. The temperature-and-frequency dependent dielectric constant and dielectric loss tangent of (La1–xHox)3Ga5SiO14 (x ≤ 0.2) and (La1–xTbx)3Ga5SiO14 (x ≤ 0.3) ceramic samples were studied in the range T = 77–700 K at frequencies f from 1 kHz to 1 MHz. Debye-type relaxation with an activation energy of about 2 eV was detected.
期刊介绍:
Inorganic Materials is a journal that publishes reviews and original articles devoted to chemistry, physics, and applications of various inorganic materials including high-purity substances and materials. The journal discusses phase equilibria, including P–T–X diagrams, and the fundamentals of inorganic materials science, which determines preparatory conditions for compounds of various compositions with specified deviations from stoichiometry. Inorganic Materials is a multidisciplinary journal covering all classes of inorganic materials. The journal welcomes manuscripts from all countries in the English or Russian language.