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Abstract: Sm:CaNb2O6 single crystal has been grown by the Czochralski method. Its high-temperature X-ray powder diffraction, optical absorption, emission spectroscopic as well as lifetime have been studied. Thermal expansion coefficients (α), J–O parameters (Ω i ), radiative lifetime (τ rad), branching ratios (β) and stimulated emission cross-sections (σ e) were calculated. The quantum efficiency (η) was calculated to be 97%. The intense peak emission cross section at 610, 658nm were calculated to be 2.40×10−21, 2.42×10−21 cm2. These results indicate that Sm:CaNb2O6 crystal has potential use in visible laser and photonic devices area. [Copyright &y& Elsevier]

This study aims to investigate the role of Y 3+ ion on microstructure, optical transmittance, and thermal properties of CaF 2 transparent ceramics. Series of nanosized CaF 2 powders doped with different concentration of Y 3+ ion were synthesized by direct precipitation method. XRD, FSEM and TEM results demonstrated that the CaF 2 nanoparticles could be tuned in size through doping of Y 3+ ion. Corresponding CaF 2 transparent ceramics were fabricated by hot-pressed (HP) method. Compared with the undoped CaF 2 sample, the transmittance of the CaF 2 ceramics improved dramatically after doping with Y 3+ ions and reached above 80% at the wavelength of 1200 nm. The effects of Y 3+ ion on the microstructure and thermal properties of CaF 2 transparent ceramics were also investigated. Overall consideration of the transmittance and thermal properties of the samples, the optimal concentration of Y 3+ ion was about 1 at.%. [ABSTRACT FROM AUTHOR]