Broadband and gain-flattened Er3+-doped tellurite fibre amplifier constructed using a gain equaliser

Abstract
The authors have constructed a broadband and gain-flattened Er3+-doped tellurite fibre amplifier by using a Mach-Zehnder type optical filter as a gain equaliser. They obtained a 3 dB down bandwidth of 68 nm in the 1536 – 1604 nm wavelength region.