Gain measurements of Mn5+(3<i>d</i>2) doped Sr5(PO4)3Cl and Ca2PO4Cl

Abstract

We report the room-temperature near-infrared emission (1.0–1.4 μm), the fluorescence lifetimes, and the gain measurements of the tetraoxo manganese specie MnO3−4(Mn5+,3d2) in single crystals of Sr5(PO4)3Cl and Ca2PO4Cl. The relatively long fluorescence lifetimes, 100 and 425 μs for MnO3−4 doped Ca2PO4Cl and MnO3−4 doped Sr5(PO4)3Cl, respectively, are consistent with the emission originating from 1E level. The stimulated emission cross section of Ca2PO4Cl:Mn5+ at around 1.15 μm is found to be 3.2×10−20 cm−2.