Laser-emission cross sections of MeNdP4O12 (Me=Li, Na, K) crystals

Emission cross sections of a Nd stoichiometric laser crystal LiNdP4O12 at 1.048 μm were measured by a direct absorption method and the conventional spectroscopic method. The largest effective-emission cross section was determined to be σbeff= (1.7±0.2) ×10−19 cm2 by these two methods. Emission cross sections of NaNdP4O12, KNdP4O12 and LiNd0.1Ln0.9P4O12 (Ln=Gd, La) were also determined by the conventional spectroscopic method. The radiative lifetime of LiNdP4O12 was calculated from the fluorescence spectra and the quantum efficiency of LiNdP4O12 was found to be 0.34.