Patent ID: 7539308

Claim:
A method of detecting at least one bit of information, the bit of information being manifested on entangled photons, the method comprising: producing entangled photons, the entangled photons comprising a first photon and a second photon, the first photon entangled with the second photon; modulating at least one bit of information onto at least one entangled photon parameter to produce modulated entangled photons, wherein the parameter is an entanglement time, a relative frequency of the first photon and the second photon, a polarization of the first photon and the second photon, a sum of frequencies of the first photon and the second photon, or a momentum of the first photon and the second photon; transmitting the modulated entangled photons; receiving at least a portion of the modulated entangled photons; detecting a value of the at least one entangled photon parameter in at least one set of entangled photons received by said receiving, wherein said detecting comprises detecting an entangled photon absorption by a material configured to absorb entangled photons and be substantially transparent to random photons; and discerning the at least one bit of information based on said detecting.