NON-LINEAR OPTICAL INTERFEROMETER WITH SATURATED AMPLIFIER

摘要

An optical transmission system includes: an interferometer (2) and a source of optical signals (24). The interferometer (2) which comprises a four-port optical coupler (4) having first and second input ports (6 and 8) and first and second output port (10 and 12), a silica optical fibre (14) coupling the first and second output ports (10 and 12) which exhibits the Kerr optical non-line-arity, and an erbium fibre optical amplifier (18) situated asymmetrically between the output ports (10 and 12). The source of optical signals (24) is coupled to the first input port (6) of the interferometer (2), The system is operated in a regime in which the optical signals saturate the amplifier (18) thereby suppressing any oscillatory output, and their power is sufficient to switch an input signal coupled to the first input port (6) to the second input port (8). This provides pulse shaping and amplification characteristics which are relatively insensitive to the input power of the optical signals from the optical source (24).