Photoluminescence of Ga 2S 3 and Ga 2S 3: Mn single crystals

Abstract

Photoluminescence spectra of Ga 2S 3 and Ga 2S 3 : Mn single crystals prepared by the chemical transport reaction method were investigated. We observed a relatively narrow band at 2.14 eV (514 nm) and a broad band centered at 1.81 eV (685 nm) for Ga 2S 3 at 10 K. For Ga 2S 3 : Mn, on the other hand, a dominant emission band at 1.81 eV (685 nm) and three weak emission bands at 2.34 (530), 2.14 (579) and 1.54 eV (805 nm) are observed. The origins of the emission bands are identified on the basis of the energy-band scheme proposed from the measurements of optical absorption, TSC and PICTS. The results show that two emission bands for Ga 2S 3 are attributed to the electron transition from the donor level to the acceptor levels, and four emission bands for Ga 2S 3 : Mn are associated with the transitions from the excited state 4T 1( 4G) of Mn 2+ to the ground state 6A 1( 6S) and the acceptor levels.