O+E-band Transmission over 50-km SMF using A Broadband Bismuth Doped Fibre Amplifier

Ultra-wideband (UWB) transmission over single-mode fibres (SMFs) is an attractive route in optical transmission, since it allows the available low-loss bandwidth offered in conventional silica SMFs to be utilised more efficiently [1] – [3] . However, data transmission beyond a single span over wavelengths outside the erbium gain band remains challenging, primarily because of the lack of suitable optical amplifiers. Recently, the emergence of bismuth-doped fibre amplifiers (BDFAs) has shown considerable potential for amplified high-speed data communications outside the C+L-bands [4] – [8] . An exciting recent work has reported the development of a BDFA exhibiting a 115nm gain bandwidth, covering the range 1345-1460nm [8] . In this paper, we demonstrate the first data transmission experiment utilising this BDFA as a booster amplifier, and we study its performance across this entire gain band.