Patent ID: 7079731

Claim:
An all-optical bistable device, comprising: a) a splitting device having first and second inputs and first and second outputs, for receiving first light beam at said first input and directing said first beam as second and third beams propagating through respective first and second outputs; b) first optical path between said first output and said second input and second optical path between said second output and said second input for creating combined optical path for said first and said second beams at said second input; c) said combined optical path includes a saturable optical amplifier for enhancing and diminishing one of said second and said third beams for driving said optical amplifier into a saturation state to create one of two stable states in which one of said second and said third beams is an enhanced beam and the other beam is a diminishing beam; d) at least one tapping device for tapping output signal from one of said first and said second optical paths, and e) at least one coupling device for coupling input signal into one of said first and said second optical paths to flip between said two stable states by converting said enhanced beam into said diminishing beam.