Optical signal regenerator and optical communications system incorporating same

A method of regenerating an optical information signal, comprising:

• configuring a resonant, non-linear, optical amplifier including gain material for providing optical gain, to exhibit bistability with a power threshold between a first relatively low power output state and a second relatively high power output state;
• generating optical clock pulses at an optical power just below the optical power bistability threshold of the amplifier;
• coupling the optical clock pulses to the resonant amplifier in a resonant mode thereof;
• and
• coupling information pulses to the amplifier in a non-resonant mode thereof;
• whereby bistable switching to one of said power states occurs upon an initial concurrent occurrence of an information pulse and a clock pulse, with subsequent bistable switching to the other of the power states occurring when the clock pulse is terminated.

An optical signal regenerator comprising:

• a resonant, non-linear, optical amplifier including gain material for providing optical gain, and capable of exhibiting bistability at a first wavelength;
• a clock signal generator for generating optical clock signals at the first wavelength and at an optical power just below the optical power bistable threshold of the amplifier at the first wavelength;
• and
• a first and a second optical coupling means for coupling the optical clock signals and an information signal to the amplifier in a resonant mode and a non-resonant mode of the amplifier, respectively;
• in which the clock signals and the information signal have different frequencies;
• and
• in which the second optical coupling means comprises a frequency dependent polarising beam splitter located within the resonator cavity so that the amplifier cannot resonate at the frequency of the information wavelength.

An optical signal regenerator comprising:

• a resonant, non-linear, optical amplifier including gain material for providing optical gain, and capable of exhibiting bistability at a first wavelength;
• a clock signal generator for generating optical clock signals at the first wavelength and at an optical power just below the optical power bistable threshold of the amplifier at the first wavelength;
• and
• a first and a second optical coupling means for coupling the optical clock signals and an information signal to the amplifier in a resonant mode and a non-resonant mode of the amplifier, respectively;
• in which the clock signals and the information signals are in orthogonal spatial modes.

An optical signal regenerator comprising:

• a resonant, non-linear, optical amplifier including gain material for providing optical gain, and capable of exhibiting bistability at a first wavelength;
• a clock signal generator for generating optical clock signals at the first wavelength and at an optical power just below the optical power bistable threshold of the amplifier at the first wavelength;
• and
• a first and a second optical coupling means for coupling the optical clock signals and an information signal to the amplifier in a resonant mode and a non-resonant mode of the amplifier, respectively;
• in which the clock signals and the information signal are in orthogonal polarisation modes.