Optical properties of MnAl2S4 and MnAl2Se4 single crystals

MnAl2S4 and MnAl2Se4 single crystals were grown by the chemical transport r eaction method. Optical energy gaps of the MnAl2S4 and MnAl2Se4 single crys tals were 3.75 and 3.21 eV, respectively, at 300 K. Emission peaks due to d onor-acceptor pair recombinations were observed at 450 and 603 nm in the Mn Al2S4 single crystal and at 488 and 655 nm in the MnAl2Se4 single crystal. Optical absorption peaks and emission peaks described as appearing due to M n2+ ion sited in T-d symmetry were observed at 414, 450, 482, and 527 nm in the MnAl2S4 single crystal and at 416, 455, 488, and 532 nm in the MnAl2Se 4 single crystal. (C) 1999 American Institute of Physics. [S0021-8979(99)03 118-7].