Crystal growth, structure and laser performance of a new Yb3+:KBaY(MoO4)3 crystal

Abstract

A Yb3+:KBaY(MoO4)3 (Yb3+:KBYM) crystal with dimensions of 51 mm × 27 mm × 10 mm was successfully grown by the TSSG method. The characteristics of the crystal structure and probability of good optical properties were analyzed. The absorption and emission spectra of Yb3+:KBYM crystal exhibit broadened bands, with the maximum absorption cross-sections of 1.17 × 10-20, 1.44 ×10-20 and 1.37 × 10−20 cm2 at 976 nm for X-, Y- and Z-polarizations, respectively. The corresponding absorption FWHMs are as wide as 77, 46 and 55 nm. The well-known re-absorption effect of Yb3+ in the crystal is discussed. Two methods, the Füchtbauer-Ladenburg method (FL) and reciprocity method (RM) were adopted to compute the emission cross-sections and results show a certain discrepancy but the errors are allowable. The laser potentiality of the Yb3+:KBYM crystal was also evaluated by calculations of minimum inversion fraction βmin, saturation pump intensity Isat, the minimum pump intensity Imin and gain cross-sections spectra. Laser experiment was carried out and Watt-level continuous wave laser has been realized. Results indicate that the Yb3+:KBYM crystal with a disordered structure may be a potential laser media that can be used to generate tunable and ultrashort pulse laser emissions with high quality beam.