Luminescence of Bi3+-doped crystals of Cs2NaYBr6 and Cs2NaLaCl6

The luminescence properties of Cs2NaYBr6Bi3+ and Cs2NaLaCl6Bi3+ crystals are reported. Emission is observed from isolated Bi3+ ions and from Bi3+ pairs. For the isolated Bi3+ ion the emissions are in the ultraviolet region. Excitation in the A band yields only 3T1u emission in case of Cs2NaYBr6Bi3+ and 3T1u and 3A1u emission in case of Cs2NaLaCl6Bi3+. Decay time measurements as a function of temperature are also reported.