PHOTOLUMINESCENCE PROPERTIES OF ZNGA2O4-MN POWDER PHOSPHORS

The results of a systematic photoluminescence study of ZnGa2O4:Mn powder phosphor are reported. At room temperature this phosphor exhibits bright, green luminescence with a spectral peak at 2.46 eV and Commission International de l'Eclairage chromaticity coordinates of x=0.073 and gamma=0.696. At low temperatures the luminescence was found to consist of three components assigned to the T-4(1)-(6)A(1) inner transition of the 3d electrons of Mn2+ ions located on three different sites of the host crystal. Selective excitation and lifetime measurements were used to investigate the assignment of these features. The photoluminescence lifetime showed a single exponential decay of about 4 ms and at T=1.6 K an optical-phonon-related fine structure [E(phonon)=(8.2+/-0.2) meV] of the main photoluminescence line was observed. (C) 1995 American Institute of Physics.