OPTICAL SPECTROSCOPY PROPERTIES OF BALIF3 DOPED WITH NI-2+

The basic optical properties of a new perovskite crystal, BaLiF3, doped with Ni2+ are reported. We have identified several absorption bands belonging to the Ni2+ in an octahedral site by the direct adsorption spectrum as well as by the excitation spectrum. The main absorption band peaks at 1180 nm with a DELTAE/E almost-equal-to 30%, showing very well defined sharp lines, at low temperature, due to spin-orbit splitting of the excited state. By pumping in any of the absorption bands, a strong emission band peaking at 1.5 mum (DELTAE/E almost-equal-to 20%) is observed, with a decay time at room temperature of 3 ms. Besides the 1.5 mum emission band, two other bands were observed, peaking at 480 and 740 nm. All the observed energy transitions are in good agreement with the Tanabe-Sugano model and the measured cross-sections are in the range of the expected ones for allowed magnetic dipole transitions.