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Detecting correlated errors in twin-field quantum key distribution
We experimentally demonstrate that we can detect correlated errors in a twin-field quantum key distribution (TFQKD) system by using a technique that is related to self-consistent tomography. We implement a TFQKD system based on a fiber-Sagnac loop, in which Alice and Bob encode information in the phase of weak coherent states that propagate in opposite directions around the loop. These states interfere as they exit the loop and are detected by a third party, Charlie, who reports the results of their measurements to Alice and Bob. We find that it is possible for Alice and Bob to detect correlated state-preparation and measurement errors while trusting only their own individual states, and without trusting Charlie’s measurements.
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- Award ID(s):
- 1855174
- PAR ID:
- 10390662
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 40
- Issue:
- 2
- ISSN:
- 0740-3224; JOBPDE
- Format(s):
- Medium: X Size: Article No. 279
- Size(s):
- Article No. 279
- Sponsoring Org:
- National Science Foundation
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