Time–energy high-dimensional one-side device-independent quantum key distribution

Compared with full device-independent quantum key distribution（DI-QKD）, one-side device-independent QKD（1s DI-QKD） needs fewer requirements, which is much easier to meet. In this paper, by applying recently developed novel time–energy entropic uncertainty relations, we present a time–energy high-dimensional one-side device-independent quantum key distribution（HD-QKD） and provide the security proof against coherent attacks. Besides, we connect the security with the quantum steering. By numerical simulation, we obtain the secret key rate for Alice＇s different detection efficiencies. The results show that our protocol can performance much better than the original 1s DI-QKD. Furthermore, we clarify the relation among the secret key rate, Alice＇s detection efficiency, and the dispersion coefficient. Finally, we simply analyze its performance in the optical fiber channel.

Measurement-device-independent quantum cryptographic conferencing with an untrusted source

Measurement-device-independent quantum cryptographic conferencing（MDI-QCC） protocol puts MDI quantum key distribution（MDI-QKD） forwards to multi-party applications, and suggests a significant framework for practical multi-party quantum communication. In order to mitigate the experimental complexity of MDI-QCC and remove the key assumption（the sources are trusted） in MDI-QCC, we extend the framework of MDI-QKD with an untrusted source to MDI-QCC and give the rigorous security analysis of MDI-QCC with an untrusted source. What is more, in the security analysis we clearly provide a rigorous analytical method for parameters＇ estimation, which with simple modifications can be applied to not only MDI-QKD with an untrusted source but also arbitrary multi-party communication protocol with an untrusted source. The simulation results show that at reasonable distances the asymptotic key rates for the two cases（with trusted and untrusted sources） almost overlap, which indicates the feasibility of our protocol.

Asymmetric Decoy State Measurement-Device-Independent Quantum Cryptographic Conferencing

Measurement-device-independent quantum cryptographic conferencing （MDI-QCC） protocol suggests an important scheme for practical multiparty quantum communication. As far as we know, MDI-QCC or MDI-quantum key distribution protocols always assume that the decoy state strategies used at each user＇s side are the same. In this study, to mitigate the system complexity and to improve the performance of MDI-QCC protocol in the finite-key case, we propose an asymmetric decoy state method for MDI-QCC protocol, and present security analysis and numerical simulations. From numerical simulations, our protocol can achieve better performance in the finite-key case. That is, with a finite data size of 10111011, it can achieve nonzero secret key rate over 43.6km.