Abstract
Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Photons appear to be the medium of choice for quantum communication. Owing to photon losses, robust quantum communication over long lossy channels requires quantum repeaters. It is widely believed that a necessary and highly demanding requirement for quantum repeaters is the existence of matter quantum memories. Here we show that such a requirement is, in fact, unnecessary by introducing the concept of all-photonic quantum repeaters based on flying qubits. In particular, we present a protocol based on photonic cluster-state machine guns and a loss-tolerant measurement equipped with local high-speed active feedforwards. We show that, with such all-photonic quantum repeaters, the communication efficiency scales polynomially with the channel distance. Our result paves a new route towards quantum repeaters with efficient single-photon sources rather than matter quantum memories.
Highlights
Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states
Quantum communication opens up opportunities for secure communication[1,2] and the teleportation of quantum states[3], and is an important ingredient of the quantum internet[4], which enables the distribution of entanglement over long distances
We draw our protocol from a concept, ‘time reversal’, underlying the distinguished findings in quantum information theory, such as measurement-based quantum computation[39,40] and measurement-device-independent quantum key distribution (QKD)[41]
Summary
Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Our protocol corresponds to the time reversal of the conventional quantum repeaters[4,6,7,8,9,10,11,12,13,14,15,16,17,18,19], where entanglement swapping is performed before entanglement generation.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
