Characteristics of Randomly Coupled 12-core Erbium-Doped Fiber Amplifier

A randomly coupled 12-core erbium-doped fiber amplifier (EDFA) operating in the C- or L-band is investigated. We experimentally demonstrate that both C and L-band operation can be supported with the 12-core EDFA by adjusting the erbium-doped fiber (EDF) length. Evaluations of the amplification characteristics of the proposed EDFA showed that a modal gain of more than 20 dB or 15 dB, a noise figure of about 5 dB or 6 dB, and a mode-dependent loss penalty of less than 1 dB or 2 dB were respectively obtained over the whole C-band (1530-1565 nm) or L-band (1570-1605 nm) with 8- or 60-m EDF. Transmission experiments showed the applicability of our EDFAs for inline amplified transmission systems. We also examined the impact of MDL on the power efficiency of the randomly coupled multi-core EDFA for achieving power-efficient long-distance SDM transmission.