OPTICAL FIBER AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To provide a practical optical fiber amplifier for multi-core transmission in which crosstalk between cores is suppressed by mode coupling.SOLUTION: The optical fiber amplifier includes: a multi-core fiber having two or more cores; and an amplifier input part which couples inputted two or more signal lights and excitation lights so as to enter a first end surface of the cores. The optical fiber amplifier amplifies the incident signal lights to the first end surface to generate two or more amplification signal lights and emits the amplification signal lights from a second end surface of the cores of the multi-core fiber. At least two of the cores are a first core and a second core. A propagation direction of first amplification signal light propagating in the first core is opposite to a propagation direction of second amplification signal light propagating in the second core.