Patent ID: 8554022

Claim:
An apparatus for modulating light with light, comprising: a substrate having an insulating surface; a high index contrast waveguide adjacent said insulating surface, said high index contrast waveguide having a first input port for receiving a first input light beam having a first frequency, a second input port for receiving a second input light beam having a second frequency different from said first frequency, a third input port for receiving a third input light beam with a third frequency different from at least one of said first and second frequencies, and an output port for providing an output light beam; and a graphene cladding adjacent said high index contrast waveguide; said high index contrast waveguide and said graphene cladding configured so that, when said first input light beam is provided as a first continuous-wave laser beam having a first frequency, and said second input light beam is provided as a second continuous-wave laser beam having a second frequency, said output light beam appearing at said output port includes a modulated signal at said third frequency having a modulation frequency equal to a difference between said first frequency of said first input light beam and said second frequency of said second input light beam.