Optical amplifier and related device

An optical communication device, comprising an optical amplifier, the optical amplifier comprising:

• a first gain medium, a second gain medium, a first multiplexer/demultiplexer, and a second multiplexer/demultiplexer, wherein the second multiplexer/demultiplexer is connected to the first gain medium;
• the second multiplexer/demultiplexer is configured to output, to the first gain medium in a coupling manner, a first optical signal and first gain clamping light output by the first multiplexer/demultiplexer, wherein the first optical signal is an input optical signal of the optical amplifier, or is an optical signal obtained by amplifying the input optical signal of the optical amplifier;
• the first gain medium is configured to:
• amplify the first optical signal, and perform gain clamping on the first optical signal based on the first gain clamping light, to obtain target light, wherein the target light is light obtained by amplifying the first optical signal through the first gain medium;
• the second gain medium is configured to amplify the target light or the target light amplified through a target gain medium;
• and
• the first multiplexer/demultiplexer is configured to separate the first gain clamping light from the target light amplified through the second gain medium.