Patent ID: 8384991

Claim:
An optical device comprising: a saturable absorber for an optical pulse, said saturable absorber including: an optical fiber waveguide for guiding said optical pulse, said optical fiber waveguide having a tapered section of reduced diameter along a length thereof that is selected to allow an external evanescent field to be formed by an optical pulse as it passes through said tapered section of said optical fiber; and a composite material surrounding said tapered section of said optical fiber, said composite material comprising a polymer mixed with a plurality of nanostructures that are selected to absorb selected wavelengths in said optical pulse, said polymer being selected to have an index of refraction that allows said evanescent field guided in the tapered section of said optical fiber to interact with the nanostructures in the composite material, whereby, saturated absorption impresses self-amplitude modulation on said optical pulse as it passes through said tapered section of said optical fiber waveguide.