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COmmunications and Networking with QUantum operationally Secure Technology for Maritime Deployment (CONQUEST)

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Technical Report,02 Sep 2016,01 Dec 2016

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BBN Technologies Cambridge United States

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Saikat Guha has been in discussions with Kamil Bradler of CipherQ Corp. on extending the proof technique of Lutkenhaus et al., PRA 79, 012307, which proved security and a rate lower bound for a binary-input BPSK CV QKD protocol. The main challenge in extending this proof technique to an M-ary is that this requires us to retain the entire relative geometry of the M purifications of the Eves states i.e., M choose 2 inner products. We are investigating a way where we could argue that the symmetry of the transmitted ensemble e.g., a M-ary PSK constellation is preserved in the symmetry of a particular purification of Eves conditional states, which lets us proceed with evaluating bounds to conditional entropies using only a few parameters that describe that geometry, and in turn will hopefully lead to a rate lower bound with a simple-to-implement key map that only has a few quantities that Alice and Bob need to estimate during the channel estimation step.

Subject Categories:

  • Quantum Theory and Relativity

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