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To overcome the low-reconciliation-efficiency problem of Gaussian modulation (GM)-based-CV-QKD, we propose to use discretized-GM-based-CV-QKD. This scheme has complexity and reconciliation-efficiency similar to discrete modulation (DM)-based-CV-QKD and at the same time solves for the problem of nonexistence of strict security proofs for DM-CV-QKD under collective attacks.
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Entanglement-Based CV-QKD with Information Reconciliation over Entanglement-Assisted Link
An entanglement-based continuous variable (CV) QKD scheme is proposed, performing information reconciliation over an entanglement-assisted link. The same entanglement generation source is used in both raw key transmission and information reconciliation. The entanglement generation source employs only low-cost devices operated in the C-band. The proposed CV-QKD scheme with information reconciliation over an entanglement-assisted link significantly outperforms the corresponding CV-QKD scheme with information reconciliation over an authenticated public channel. It also outperforms the CV-QKD scheme in which a classical free-space optical communication link is used to perform information reconciliation. An experimental demonstration over the free-space optical testbed established at the University of Arizona campus indicates that the proposed CV-QKD can operate in strong turbulence regimes. To improve the secret key rate performance further, adaptive optics is used.
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- Award ID(s):
- 2244365
- PAR ID:
- 10536991
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Entropy
- Volume:
- 26
- Issue:
- 4
- ISSN:
- 1099-4300
- Page Range / eLocation ID:
- 305
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/e26040305
