Growth, Structure, Thermal Properties and Spectroscopic Characteristics of Nd(3+)-Doped KGdP(4)O(12) Crystal

A single crystal of Nd(3+)-doped KGdP(4)O(12) was successfully grown with the top-seeded solution growth and slow cooling (TSSG−SC) technique. It crystallizes in space group C2/c with cell parameters a = 7.812(2) Å, b = 12.307(3) Å, c = 10.474(2) Å, β = 110.84(3)° and Z = 4. The IR and Raman spectra also indicated that the phosphoric polyhedra of Nd:KGdP(4)O(12) has a cyclic symmetry. The chemical composition of the crystal was analyzed and the distribution coefficient of Nd(3+) was calculated. The crystal morphology of KGdP(4)O(12) was identified using X-ray diffraction. The compound has good thermal stability to 920°C. Its specific heat and thermal conductivity were determined for potential applications. The spectral properties of Nd:KGdP(4)O(12) indicates that it exhibits broad absorption and emission bands, which are attributed to low symmetry of the crystal. The broad absorption band around 798 nm has a full-width at half-maximum (FWHM) of 14.8 nm and is suitable for AlGaAs laser diode pumping. Moreover, 5 at% Nd(3+)-doped KGdP(4)O(12) crystal has a long luminescence lifetime of 300 μs and a high quantum efficiency of 96%.