Spectral properties and energy transfer of Tm3+/Ho3+-codoped Ga2O3-Bi2O3-GeO2-PbO glasses

The 2.0 μm emission originating from Ho3+:5I7 → 5I8 transition in Ho3+/Tm3+-codoped gallate-bismuth-germanium-lead glasses were investigated upon excitation with 808 nm laser diode (LD). Energy transfer (ET) process between Tm3+: 3F4 level and Ho3+: 5I7 level was also discussed. It was noted that the measured peak wavelength and stimulated emission cross-section of Ho3+-doped bismuth-germanium-lead glasses were ∼2.02 μm and 5.1×10−21 cm2, respectively. Intense emission of Ho3+ in Tm3+/Ho3+-codoped GBPG glass were observed, which resulted from the ET between Tm3+: 3F4 and Ho3+: 5I7 level upon excitation with 808 nm LD.