Researchers at NIST have achieved a new record in quantum teleportation, transferring quantum information over 100 kilometers of optical fiber. This distance is four times greater than the previous record, demonstrating the feasibility of quantum communication over conventional fiber-optic networks. The experiment involved transferring quantum information contained in one photon’s time slot to another photon transmitted over 102 km of fiber.
The achievement was made possible by advanced single-photon detectors designed and made at NIST, which can measure the incredibly weak signal with high efficiency. The detectors, made of superconducting nanowires, can record more than 80% of arriving photons, revealing whether they are in the same or different time slots each 1 nanosecond long.
The experiment used quantum states that indicate when in a sequence of time slots a single photon arrives, and the teleportation method is novel in that four of NIST’s photon detectors were positioned to filter out specific quantum states. The successful teleportation of the desired quantum state was achieved in 83% of the maximum possible successful transmissions, on average, exceeding the mathematically significant 66.7% threshold for proving the quantum nature of the teleportation process.
This breakthrough could lead to the development of quantum repeaters that could resend data periodically in order to extend network reach, potentially enabling the construction of a “quantum internet.” The ability to perform quantum teleportation over long distances in fiber-optic lines offers more flexibility for network design compared to previous methods using free space.
Source: https://www.nist.gov/news-events/news/2015/09/nist-team-breaks-distance-record-quantum-teleportation
Keywords: Teleportation, Quantum States, Single-Photon Detectors, Quantum Repeater, Superconducting Nanowires
