A Six-Mode Erbium-Doped Fiber Amplifier
16 September 2012
We report and characterize an amplifier which provides gain to a record six spatial modes simultaneously. Two sections of erbium-doped fibre with different mode-dependent gain characteristics are concatenated to equalize gain between modes. The overall gain excursion does not exceed 4dB across all modes. The noise figure is found lower than 7dB
