Loss-Tolerant Measurement-Device-Independent QKD over Untrusted Repeaters via High-Dimensional Time-Bin Multiplexing
Abstract
We propose a loss-tolerant measurement-device-independent quantum key distribution (MDI-QKD) protocol using time-bin-multiplexed single photons entangled with local qubits stored in nitrogen-vacancy (NV) centers. In each round, Alice and Bob each send a single multiplexed photon to an untrusted intermediary, Charlie. Each photon first becomes entangled with Charlie's NV-center qubits; Charlie then performs entanglement swapping between his NV qubits to establish EPR pairs between Alice's and Bob's local qubits. With d time bins per photon, log2 d + 1 EPR pairs can be generated per transmitted photon, substantially increasing the probability of EPR-pair creation under limited channel bandwidth. To further mitigate the effects of prolonged memory storage, the protocol employs a memory-insensitive (MI) architecture, where multiple banks of qubits and multiplexed photon routing reduce the effective memory lifetime requirements. This approach enhances loss tolerance, enabling higher secret key rates and secure key distribution over longer distances compared to conventional single-photon protocols. Using the Lo-Chau EPR-QKD framework and Shor-Preskill reduction, we prove that the protocol is secure without trusting intermediate nodes, making it suitable for quantum networks with untrusted repeaters.
Related
- Independent Three-dimensional Dose Calculation from Log Files for Breast VMAT: A Measurement-free Quality Assurance Approach
- Establishing an independent measurement traceability for 60-Co Air Kerma
- Model-independent measurement of the transversity amplitudes of the B0→ K*0μ+μ- decay
- Semi-Device-Independent Certification of multi-qubit Entangled Basis Measurement
- Dalitz plot binning optimization for the model-independent measurement of the CKM angle β with B0 → D π+ π-, D → KS0 π+ π- decays
BibTeX
@misc{yin2026losstolerant,
title = {{Loss-Tolerant Measurement-Device-Independent QKD over Untrusted Repeaters via High-Dimensional Time-Bin Multiplexing}},
author = {Yu-Chun Yin and Ching-Yi Lai and Alexei Ashikhmin},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.20148},
eprint = {2610.20148},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.20148},
}
RIS
TY - UNPB
TI - Loss-Tolerant Measurement-Device-Independent QKD over Untrusted Repeaters via High-Dimensional Time-Bin Multiplexing
AU - Yu-Chun Yin
AU - Ching-Yi Lai
AU - Alexei Ashikhmin
PY - 2026
DA - 2026/10/14
PB - arXiv
DO - 10.48550/arxiv.2610.20148
UR - https://arxiv.org/abs/2610.20148
AB - We propose a loss-tolerant measurement-device-independent quantum key distribution (MDI-QKD) protocol using time-bin-multiplexed single photons entangled with local qubits stored in nitrogen-vacancy (NV) centers. In each round, Alice and Bob each send a single multiplexed photon to an untrusted intermediary, Charlie. Each photon first becomes entangled with Charlie's NV-center qubits; Charlie then performs entanglement swapping between his NV qubits to establish EPR pairs between Alice's and Bob's local qubits. With d time bins per photon, log_2 d + 1 EPR pairs can be generated per transmitted photon, substantially increasing the probability of EPR-pair creation under limited channel bandwidth. To further mitigate the effects of prolonged memory storage, the protocol employs a memory-insensitive (MI) architecture, where multiple banks of qubits and multiplexed photon routing reduce the effective memory lifetime requirements. This approach enhances loss tolerance, enabling higher secret key rates and secure key distribution over longer distances compared to conventional single-photon protocols. Using the Lo-Chau EPR-QKD framework and Shor-Preskill reduction, we prove that the protocol is secure without trusting intermediate nodes, making it suitable for quantum networks with untrusted repeaters.
ER -