High gain semiconductor optical amplifier with low noise

摘要

An optical signal amplifier includes a first semiconductor optical amplifier having an input for receiving an optical signal, and an output, wherein the optical signal is amplified by the first semiconductor optical amplifier resulting in an amplified optical signal. The optical amplifier also includes an optical signal isolator having an input in optical communication with the output of the first semiconductor optical amplifier, and an output, wherein the optical signal isolator receives the amplified signal from the first semiconductor optical amplifier and allows for transmission of an optical signal in a single direction. The optical amplifier further includes a second semiconductor optical amplifier having an input for receiving the amplified optical signal from the optical signal isolator, and an output, wherein the amplified optical signal is amplified by the second semiconductor optical amplifier resulting in a twice amplified optical signal.