Optical spectroscopy of borate glasses doped with trivalent rare-earth ions

Rare-earth doped glasses gain increasing importance in optical devices, such as fiber lasers or light emitting diodes. Luminescence properties of rare-earth ions are well-known, but quantum efficiencies have been insufficiently studied. In this work, luminescent quantum efficiencies for series of Sm3+- and/or Eu3+-doped barium borate glasses have been investigated. In Sm3+- and Eu3+-doubly-doped glasses, energy transfer processes between the two rare-earth ions become important and are discussed in detail.