Abstract: A system and method for optical communication employing entangled photons. A modulator selectively extends the optical path length of one conjugate photon of each entangled photon pair, thereby incorporating a bit value in the entangled photon pair. The entangled photon pair is transmitted and passed through a spectrometer, which separates the photons according to their frequency and directs them to a coincidence counter. A decline in a curve of a number of coincidence counts plotted against conjugate photon frequency disparity is employed to extract the bit value.

Abstract: A waveguide for decreasing signal propagation delay including an evanescent region and an amplification region. In various embodiments, the evanescent region includes varying index of refraction regions, such as one or more thin film regions and one or more fiber Bragg grating regions, one or more frustrated internal reflection constructs, or one or more undersized waveguides. In various embodiments, the amplification region includes doped amplifiers and other amplifier types that use propagated pump photons to provide amplification, or semiconductor amplifiers or other amplifier types that use electrical power to provide amplification. A method for decreasing signal propagation delay includes propagating a signal having a signal frequency into an evanescent region. After propagation through the evanescent region, amplifying the attenuated signal.