Tuning rare earth ion emission wavelength in phosphate based glasses using cerium oxide

A Nd-doped or Yb-doped or Er-doped phosphate glass composition comprising (based on mol %):

• P2O5
• 40.00-70.00
• B2O3
• 0.00-20.00
• SiO2
• 0.00-15.00
• Al2O3
• 2.00-15.00
• Nd2O3
• 0.00-5.00
• Yb2O3
• 0.00-solubility limit
• Er2O3
• 0.00-5.00
• CeO2
• 0.25-30.00
• (or an equivalent amount of Ce2O3)
• La2O3
• 0.00-29.75
• MO
• 0.00-10.00
• M′2O
• 0.00-15.00
• wherein
• MO is the sum of MgO, CaO, SrO, BaO, and ZnO,
• M′2O is the sum of Li2O, Na2O, K2O, and Cs2O,
• the sum of MO and M′2O is 0.0-15.0 mol %,
• the sum of P2O5, B2O3, SiO2, and Al2O3 is at least 46 mol %,
• all or a portion of CeO2 can be replaced by an equivalent amount of Ce2O3, in which an equivalent amount of Ce2O3 means an amount having the same number of moles of Ce as an amount of CeO2,
• the sum of La2O3, CeO2, Ce2O3, Nd2O3, Yb2O3, and Er2O3 is not more than 35.00 mol %,
• solubility limit refers to the concentration which is the limit of solubility of Yb2O3 in the glass composition,
• the glass contains SiO2 and/or B2O3, and
• the glass contains at least 0.25 mol % Nd2O3 and/or at least 0.50 mol % Yb2O3 and/or at least 0.05 mol % Er2O3.