Abstract: A system for and method of processing complex signals encoded into quantum states is presented. According to an embodiment of the invention, polarized components of a pump laser beam are separated and respectively modulated with first and second signals. The modulated polarized components are directed to adjacent non-linear crystals with optical axes aligned at right angles to each-other. Information regarding at least one of the first and second signals is then derived from measurements of coincidence events.

Abstract: A system and method of detecting entangled photon pairs, each pair including a signal photon and an idler photon, is disclosed. Entangled photon pairs are provided having an entanglement time and an entanglement area selected to substantially increase an associated entangled two-photon cross-section of an associated target medium. The entangled photon pairs are also selected to have an energy distribution between the signal photon and the idler photon to substantially decrease an associated random two-photon absorption cross section of the target medium. The entangled photon pairs are directed to the target medium, and at least one entangled-photon pair being absorbed by the target medium is detected.

Abstract: A system for and method of detecting and characterizing materials using entangled photons is presented. The material may be at a great distances from the detector and may be biological material, complex organic compounds, or inorganic chemicals. The disclosed system and method provide advantages over traditional techniques in that they are largely impervious to atmospheric reduction of probing radiation and in that less probing radiation is required. The reduced probe energy requirement allows for detecting and characterizing sensitive material with significantly reduced material bleaching compared with traditional techniques.

Abstract: A system for and method of processing complex signals encoded into quantum states is presented. According to an embodiment of the invention, polarized components of a pump laser beam are separated and respectively modulated with first and second signals. The modulated polarized components are directed to adjacent non-linear crystals with optical axes aligned at right angles to each-other. Information regarding at least one of the first and second signals is then derived from measurements of coincidence events.

Abstract: A system for and method of processing complex signals encoded into quantum states is presented. According to an embodiment of the invention, polarized components of a pump laser beam are separated and respectively modulated with first and second signals. The modulated polarized components are directed to adjacent non-linear crystals with optical axes aligned at right angles to each-other. Information regarding at least one of the first and second signals is then derived from measurements of coincidence events.

Abstract: A system for and method of detecting and characterizing materials using entangled photons is presented. The material may be at a great distances from the detector and may be biological material, complex organic compounds, or inorganic chemicals. The disclosed system and method provide advantages over traditional techniques in that they are largely impervious to atmospheric reduction of probing radiation and in that less probing radiation is required. The reduced probe energy requirement allows for detecting and characterizing sensitive material with significantly reduced material bleaching compared with traditional techniques.

Abstract: A system and method of detecting entangled photon pairs, each pair including a signal photon and an idler photon, is disclosed. Entangled photon pairs are provided having an entanglement time and an entanglement area selected to substantially increase an associated entangled two-photon cross-section of an associated target medium. The entangled photon pairs are also selected to have an energy distribution between the signal photon and the idler photon to substantially decrease an associated random two-photon absorption cross section of the target medium. The entangled photon pairs are directed to the target medium, and at least one entangled-photon pair being absorbed by the target medium is detected.