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Er3+‐doped strontium gadolinium gallium garnet (SrGdGa3O7) single‐crystal was grown by Czochralski method. The Er3+ concentration in the crystal was determined as 4.2 × 1021 ions/cm3 by inductively coupled plasma atomic absorption spectroscopy. Refractive index of the crystal was measured at the wavelengths of 633, 1311 and 1553 nm by prism coupling technique. The results show that the crystal is a positive uniaxial crystal with a birefringence of ~0.01, and the Sellmeier equation reported previously for the crystal doped with Nd3+ is also valid for the one doped with Er3+. Unpolarized absorption spectrum of the crystal was measured at room temperature and the Er3+ absorption cross‐section spectrum was calibrated from it. The Er3+ spectroscopic properties were studied by Judd‐Ofelt theory. Some fundamental spectroscopic parameters were obtained that include absorption coefficient and cross‐section spectral distributions, electronic transition oscillator strength, Judd‐Ofelt parameters, fluorescence branch ratio, transition probability, radiative and fluorescence lifetimes, and quantum efficiency. [ABSTRACT FROM AUTHOR]

Influence of factors on growth ofoff-congruent LiNbO3single-crystal by Li-rich/Li-poorchemical vapor transport equilibration(VTE) was studied. These factors include the molar ratio of raw materialsLi2CO3and Nb2O5for preparingtwo-phase crucible, the hollow space volume for VTE growth, and theperiod of use of two-phase crucible. To achieve the goal, a numberof off-congruent LiNbO3plates were grown by Li-rich/Li-poorVTE technique using four two-phase crucibles having different molarratios of raw materials, hollow space volumes, and periods of use.The VTE-induced crystal composition alteration was characterized bymeasurement of birefringence. A comparison of results of differentcrucibles shows that in the Li-rich VTE case the first factor hasless effect, while the latter two may cause a difference of Li2O content as much as 0.4 mol %. Larger hollow space volumeand older crucible tend to degrade the VTE growth efficiency. Instead,the growth by Li-poor VTE is less affected by the three factors becauseof much lower Li2O gas pressure and hence slow growth ratein comparison with that by Li-rich VTE. [ABSTRACT FROM AUTHOR]