High energy-transfer rate from Sn²⁺ to Mn²⁺ in phosphate glasses

High energy-transfer rates from Sn²⁺ to Mn²⁺ centers are demonstrated in ZnO-P₂O₅ glass. Emission decay curves of Sn²⁺ suggest an energy exchange interaction between Sn²⁺ and Mn²⁺. It is notable that the high energy-transfer rates are attained for random phosphate glass and that the transfer rate becomes slower with increasing amounts of Mn²⁺. Because these glasses possess high internal quantum efficiencies independent of the Sn²⁺ or Mn²⁺ concentration, we emphasize that effective energy-transfer paths are generated in the transparent glass phosphor, which leads to the development of a transparent inorganic light-emitting material different from conventional rare-earth-containing powdered phosphors.