A system and method for the controlled generation, manipulation, and conversion of individual photons in and for a quantum computing environment or a quantum communication environment are provided. Systems and methods for doubling a single photon in a first propagation mode into two new photons in one or two new propagation modes, combining two photons in one or two propagation modes into a single photon of a single propagation mode, and implementing a pi phase shift on a two-photon state but not on the one-photon state in a fully controlled, consistent, and repeatable fashion are also provided, as well as a source of individual photons having clearly defined and fully controllable properties. Embodiments of the above allow for generation and conversion operations that are up to 100% efficient. The generation, conversion, combination, and phase shifting operations are preferably carried out inside a non-linear χ3 material of a predetermined length.
展开▼
