Spectroscopic characteristics of Cr3+:Al2O3 polycrystalline transparent alumina ceramics

Spectral properties of transparent polycrystalline Cr3+:Al2O3 ceramics were studied. The results indicated that the absorption peaks of polycrystalline Cr3+:Al2O3 ceramics co incide with the absorption spectrum of a ruby single crystal. The crystal field and Racah parameters were calculated according to the Tanabe-Sugano energy level diagram and absorption spectra. The crystal field intensity of Cr3+: Al2O3 polycrystalline ceramics is almost the same as that of Cr3+:Al2O3 single crystal, and the character istics of the emission spectra still retains the R-line emission even as the Cr3+ concentration increases up to 0.8wt%. In particular, one 670nm emis sion peak of Cr3+ was first found in the polycrystalline ceramics.