Crystal Growth and Optical and Spectroscopic Characterization of the Ytterbium-Doped Laser Molybdate Yb-Li3Gd3Ba2(MoO4)8

Because of the existence of a phase transition at temperatures lower than the melting point, Yb-doped Li 3 Gd 3 Ba 2 (MoO 4 ) 8 was grown by the top seeded solution growth slow cooling method using Li 2 Mo 2 O 7 as flux. At room temperature, the crystal possesses monoclinic symmetry with space group C2/c (No. 15), with lattice parameters a = 5.2355(3) A, b = 12.7396(8) A, c = 19.1626(11) A, and β = 91.170(1)°, and only one 8f crystal site for Yb 3+ , which is shared with Li + and Gd 3+ cations. The information provided by the low temperature (6 K) spectroscopy indicates crystal field splittings of 0, 223, 353, and 460 cm -1 and 10248, 10413, and 10634 cm -1 for 2 F 7/2 and 2 F 5/2 Yb 3+ manifolds, respectively, and the spectral broadening observed is attributed to locally disordered environments around the 8f Yb 3+ centers. Ultraviolet and infrared optical absorption edges of this biaxial laser crystal also were characterized.