| We have developed and characterized the preliminary network components necessary to realize practical quantum telecommunications in the 1310-nm O-band of the existing fiber optic infrastructure. Quantum network components available, at classical-telecommunicationsspeed, in the O-band would allow single-photon-level quantum data to be multiplexed with the bright 1550-nm C-band data that the telecommunications infrastructure already supports, therefore enabling quantum information---be it for quantum computing, cryptography, games or other purposes---to be easily distributed to remote parties.;Two necessary network components are presented: a high-quality source of O-band entangled photon pairs and a switch capable of routing single photons while preserving the entanglement between the photon and its partner. The pairs are created in standard optical fiber, allowing for near-lossless coupling to the existing telecommunications infrastructure. The method used is also scalable, both in creating future identical sources and operating at much higher repetition rates. Such higher rates will ensure that a meaningful number of entangled photon pairs survive distribution, which is inherently lossy (though fiber optics minimize this loss over long distances). The other component required to establish a network more advanced than a point-to-point link is a single-photon switch. In order to successfully implement such a switch for the quantum data of interest, the design must be able to switch single-photon level signals with very low loss and near unity probability of success. It is capable of operating at network speeds while preserving the photon's quantum state. |
