Growth, improved thermal stability and spectral properties of Yb~(3+)-ions doped high temperature phase α-Ba_3Gd(BO_3)_3 crystals co-doped by Sr~(2+), Ca~(2+) and La~(3+) ions

摘要

To investigate the cause of the thermal instability of Yb3+-ions doped Ba3Gd(BO3)(3) crystal grown from Czochralski technique, the low temperature phase beta-Ba3Gd(BO3)(3) powder was synthesized at the temperature of 800 degrees C. To inhibit the phase transition of high temperature phase Yb-alpha-Ba3Gd(BO3)(3) during the crystal growth process, co-doping ions Sr2+, Ca2+ and La3+ ions were introduced in Yb:alpha-Ba3Gd(BO3)(3) crystal. The melting point increased and the thermal stability of Yb:alpha-Ba3Gd(BO3)(3) crystal was improved by co-doping ions. The absorption peaks of co-doped crystals centered at 976 nm with FWHM of 11, 11 and 12 nm and the absorption cross sections were 3.40 x 10(-21) cm(2), 4.00 x 10(-21) cm(2) and 2.66 x 10(-21) cm(2), respectively. The emission cross sections at 1040 nm were 2.19 x 10(-21) cm(2), 2.53 x 10(-21) cm(2) and 1.93 x 10(-21) cm(2), respectively. The fluorescence times of co-doped by Sr2+, Ca2+ and La3+ ions were shorter than that of Yb:alpha-Ba3Gd(BO3)(3) crystal. So Yb:alpha-Ba3Gd(BO3)(3) crystals co-doped by Sr2+, Ca2+ and La3+ ions will be more suitable for LD-pumping laser. (C) 2017 Elsevier B.V. All rights reserved.