The infrared emission spectra and decay lifetimes of Tm3+-doped and Tm3+-Ho3+, Tm3+-Yb3+ co-doped tellurite fibres were measured using 808 nm and 978 nm diode laser pump sources in the range 1.35 μm to 2.2 μm. The spectra were compared with varying fibre lengths and core diameters. Tm3+-doped fibre shows strong emission at ∼1.8 μm and when co-doped with Ho3+, energy transfer results in strong Ho3+ fluorescence at ∼2.0 μm. These fibres show promise for compact mid-IR fibre laser sources. © 2007 Optical Society of America.