Enhancement in pump inversion efficiency at 980 nm in Er(3+), Er(3+)/Eu(3+)+ and Er(3+)/Ce(3+) doped tellurite glass fibers.

Amplification properties have been compared in Er(3+), Er(3+)/Eu(3+) and Er(3+)/Ce(3+) doped tellurite glass fibers using a 980 nm pumping scheme. The pump efficiency has been compared in the 3 types of fibers. Er(3+) ion upconversion in bulk glasses and fibers in visible range has been measured and the Er(3+) ion IR fluorescence intensity and lifetimes have been recorded to understand the amplification characteristics. Codoping with Ce3+ is more efficient in Er(3+) doped tellurite fibre.