Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review Letters

Free-Space and Fiber-Integrated Measurement-Device-Independent Quantum Key Distribution under High Background Noise

Yu-Huai Li, Shuang-Lin Li, Xiao-Long Hu, Cong Jiang, Zong‐Wen Yu, Wei Li, Wei-Yue Liu, Sheng‐Kai Liao, Ji-Gang Ren, Hao Li, Lixing You, Zhen Wang, Juan Yin, Feihu Xu, Qiang Zhang, Xiang‐Bin Wang, Yuan Wen Cao, Cheng-Zhi Peng, Jian-Wei Pan

Published Sep 6, 2023• 40 citations
Publisher

Abstract

Measurement-device-independent quantum key distribution (MDI QKD) provides immunity against all attacks targeting measurement devices. It is essential to implement MDI QKD in the future global-scale quantum communication network. Toward this goal, we demonstrate a robust MDI QKD fully covering daytime, overcoming the high background noise that prevents BB84 protocol even when using a perfect single-photon source. Based on this, we establish a hybrid quantum communication network that integrates free-space and fiber channels through Hong-Ou-Mandle (HOM) interference. Additionally, we investigate the feasibility of implementing HOM interference with moving satellites. Our results serve as a significant cornerstone for future integrated space-ground quantum communication networks that incorporate measurement-device-independent security.

DOI
10.1103/physrevlett.131.100802

Related papers

Long-Distance Free-Space Measurement-Device-Independent Quantum Key Distribution

Yuan Wen Cao, Yu-Huai Li, Kui-Xing Yang +20 more

Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted relays. Since the MDI-QKD protocol was proposed, fiber-based implementations aimed at longer distance, higher key rates, and network verification have been rapidly developed. However, owing to the effect of atmospheric turbulence, MDI-QKD over a free-space channel remains experimentally challenging. Herein, by developing a robust adaptive optics system, high-precision time synchronization and frequency locking between independent photon sources located far apart, we realized the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step toward satellite-based MDI-QKD. Moreover, the technology developed herein opens the way to quantum experiments in free space involving long-distance interference of independent single photons.

arXiv:2006.05088•Physical Review Letters•Dec 23, 2020•173 citations

Measurement-Device-Independent Quantum Key Distribution With Hybrid Integrated Self-Injection Locking Lasers

Xiao-Lei Jiang, Y P Guo, Yan-Yang Zhou +9 more

Breakthroughs in chip integration technology have accelerated the practical deployment and scalable implementation of quantum key distribution (QKD). On-chip quantum light sources are critical components of fully integrated QKD systems. Measurement-Device-Independent QKD (MDI-QKD) offers significant advantages in network communication by eliminating vulnerabilities to side-channel attacks at the detector side, while relying on high-visibility Hong-Ou-Mandel interference between photons emitted by two independent lasers. Here, we present an innovative design of the silicon-based hybrid integrated self-injection locking (SIL) laser chip that achieves high-frequency-stability operation with the frequency detuning between independent lasers suppressed to within 15 MHz, enabling high-visibility HOM interference in MDI-QKD. Leveraging this design, we experimentally demonstrate a loss-tolerant MDI-QKD system employing the setting-choice-independent correlation security framework explicitly accounting for state-preparation uncertainty. The system achieves a finite-key secret rate of 17 b/s under 34 dB channel loss (or 170-km standard fiber), surpassing previously reported MDI-QKD experiments that incorporated state preparation uncertainty under equivalent transmission loss conditions. Our result makes a promising contribution to practical applications of fully integrated quantum communication networks.

Journal of Lightwave Technology•Jun 2, 2026•1 citation

Feasibility of space-based measurement-device-independent quantum key distribution

Xingyu Wang, Chen Dong, Shanghong Zhao +3 more

Abstract The measurement-device-independent (MDI) quantum key distribution (QKD) is considered to be an alternative to overcome the currently trusted satellite paradigm. However, the feasibility of the space-based MDI-QKD remains unclear in terms of the factors: the high-loss uplink between a ground station and a satellite, the limited duration when two ground stations are simultaneously visible, as well as the rigorous requirements for the two-photon interference when performing the Bell-state measurement. In this paper, we present a feasibility assessment of space-based MDI-QKD based on the Micius satellite. Integrated with the orbital dynamics model and atmosphere channel model, a framework is presented to explore the whole parameters space including orbit height, elevation angle, apertures of transceiver and atmospheric turbulence intensity to give the considerations for improving key rates and subsequently provide a relevant parameter tradeoff for the implementation of space-based MDI-QKD. We further investigate the heart of MDI-QKD, the two-photon interference considerations such as the frequency calibration and time synchronization technology against Doppler shift, and the way of performing the intensity optimization method in the dynamic and asymmetric channels. Our work can be used as a pathfinder to support decisions involving as the selection of the future quantum communication satellite missions.

arXiv:2012.14554•New Journal of Physics•Apr 1, 2021•19 citations

Measurement-device-independent quantum key distribution with entanglement-assisted linear Bell state measurement

Cheng 诚 Zhang 张, Cheng Liu, Jiawei Ying +7 more

Abstract Measurement-device-independent quantum key distribution (MDI QKD) provides inherent immunity against attacks targeting practical measurement devices. Existing MDI QKD protocols all rely on Bell-state measurements (BSM) to establish correlations between the users. However, the success probability of linear-optics BSM is limited to 50%, which severely restricts the achievable key rate of MDI QKD. We propose a high-capacity MDI QKD protocol with entanglement-assisted linear-optical BSM. This protocol has three advantages. First, compared with the original MDI QKD, at least a 25% increase in the key rate can be achieved. Second, simulation results show that this protocol can effectively increase the maximum photon transmission distance of MDI QKD from 262 km to 272 km. Third, this protocol is feasible in a fully linear-optical system under current experimental conditions. Our protocol provides a potential approach for improving the performance of future quantum communication networks.

Chinese Physics B•Jan 9, 2026•1 citation

Side-Channel Free Measurement-Device- Independent Quantum Key Distribution Based on Source Monitoring

Wenlin Wang, Xingyu Zhou, Ming-Shuo Sun +2 more

Measurement-device-independent quantum key dis-tribution (MDI-QKD) can remove all detector side-channel attacks. However, there are still some assumptions on source preparations in MDI-QKD protocols, which are too strict to achieve in real-life implementations. To remove those assump-tions, here we construct a scheme on characterizing the source modulation errors with Hong-Ou-Mandel (HOM) interferences. Furthermore, we combine it with the decoy-state method and present the security analysis. Besides, finite data-size effects are taken into account as well. Simulation results verify the feasibility and practicability of this scheme. It thus seems a very promising candidate for constructing high-security network in the near future.

IEEE photonics journal•Aug 21, 2023•5 citations

Measurement-device-independent quantum key distribution coexisting with classical communication

Raju Valivarthi, Prathwiraj Umesh, Caleb John +6 more

Abstract The possibility for quantum and classical communication to coexist on the same fiber is important for deployment and widespread adoption of quantum key distribution (QKD) and, more generally, a future quantum internet. While coexistence has been demonstrated for different QKD implementations, a comprehensive investigation for measurement-device independent (MDI) QKD—a recently proposed QKD protocol that cannot be broken by quantum hacking that targets vulnerabilities of single-photon detectors—is still missing. Here we experimentally demonstrate that MDI-QKD can operate simultaneously with at least five 10 Gbps bidirectional classical communication channels operating at around 1550 nm wavelength and over 40 km of spooled fiber, and we project communication rates in excess of 10 THz when moving the quantum channel from the third to the second telecommunication window. The similarity of MDI-QKD with quantum repeaters suggests that classical and generalized quantum networks can co-exist on the same fiber infrastructure.

arXiv:1905.00465•Quantum Science and Technology•Jul 1, 2019•46 citations
Measurement-device-independent quantum key distribution (MDI QKD) provides immunity against all attacks targeting measurement devices. It is essential to implement MDI QKD in the future global-scale quantum communication network. Toward this goal, we demonstrate a robust MDI QKD fully covering daytime, overcoming the high background noise that prevents BB84 protocol even when using a perfect single-photon source. Based on this, we establish a hybrid quantum communication network that integrates free-space and fiber channels through Hong-Ou-Mandle (HOM) interference. Additionally, we investigate the feasibility of implementing HOM interference with moving satellites. Our results serve as a significant cornerstone for future integrated space-ground quantum communication networks that incorporate measurement-device-independent security.
Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted relays. Since the MDI-QKD protocol was proposed, fiber-based implementations aimed at longer distance, higher key rates, and network verification have been rapidly developed. However, owing to the effect of atmospheric turbulence, MDI-QKD over a free-space channel remains experimentally challenging. Herein, by developing a robust adaptive optics system, high-precision time synchronization and frequency locking between independent photon sources located far apart, we realized the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step toward satellite-based MDI-QKD. Moreover, the technology developed herein opens the way to quantum experiments in free space involving long-distance interference of independent single photons.
Breakthroughs in chip integration technology have accelerated the practical deployment and scalable implementation of quantum key distribution (QKD). On-chip quantum light sources are critical components of fully integrated QKD systems. Measurement-Device-Independent QKD (MDI-QKD) offers significant advantages in network communication by eliminating vulnerabilities to side-channel attacks at the detector side, while relying on high-visibility Hong-Ou-Mandel interference between photons emitted by two independent lasers. Here, we present an innovative design of the silicon-based hybrid integrated self-injection locking (SIL) laser chip that achieves high-frequency-stability operation with the frequency detuning between independent lasers suppressed to within 15 MHz, enabling high-visibility HOM interference in MDI-QKD. Leveraging this design, we experimentally demonstrate a loss-tolerant MDI-QKD system employing the setting-choice-independent correlation security framework explicitly accounting for state-preparation uncertainty. The system achieves a finite-key secret rate of 17 b/s under 34 dB channel loss (or 170-km standard fiber), surpassing previously reported MDI-QKD experiments that incorporated state preparation uncertainty under equivalent transmission loss conditions. Our result makes a promising contribution to practical applications of fully integrated quantum communication networks.
Abstract The measurement-device-independent (MDI) quantum key distribution (QKD) is considered to be an alternative to overcome the currently trusted satellite paradigm. However, the feasibility of the space-based MDI-QKD remains unclear in terms of the factors: the high-loss uplink between a ground station and a satellite, the limited duration when two ground stations are simultaneously visible, as well as the rigorous requirements for the two-photon interference when performing the Bell-state measurement. In this paper, we present a feasibility assessment of space-based MDI-QKD based on the Micius satellite. Integrated with the orbital dynamics model and atmosphere channel model, a framework is presented to explore the whole parameters space including orbit height, elevation angle, apertures of transceiver and atmospheric turbulence intensity to give the considerations for improving key rates and subsequently provide a relevant parameter tradeoff for the implementation of space-based MDI-QKD. We further investigate the heart of MDI-QKD, the two-photon interference considerations such as the frequency calibration and time synchronization technology against Doppler shift, and the way of performing the intensity optimization method in the dynamic and asymmetric channels. Our work can be used as a pathfinder to support decisions involving as the selection of the future quantum communication satellite missions.
Abstract Measurement-device-independent quantum key distribution (MDI QKD) provides inherent immunity against attacks targeting practical measurement devices. Existing MDI QKD protocols all rely on Bell-state measurements (BSM) to establish correlations between the users. However, the success probability of linear-optics BSM is limited to 50%, which severely restricts the achievable key rate of MDI QKD. We propose a high-capacity MDI QKD protocol with entanglement-assisted linear-optical BSM. This protocol has three advantages. First, compared with the original MDI QKD, at least a 25% increase in the key rate can be achieved. Second, simulation results show that this protocol can effectively increase the maximum photon transmission distance of MDI QKD from 262 km to 272 km. Third, this protocol is feasible in a fully linear-optical system under current experimental conditions. Our protocol provides a potential approach for improving the performance of future quantum communication networks.
Measurement-device-independent quantum key dis-tribution (MDI-QKD) can remove all detector side-channel attacks. However, there are still some assumptions on source preparations in MDI-QKD protocols, which are too strict to achieve in real-life implementations. To remove those assump-tions, here we construct a scheme on characterizing the source modulation errors with Hong-Ou-Mandel (HOM) interferences. Furthermore, we combine it with the decoy-state method and present the security analysis. Besides, finite data-size effects are taken into account as well. Simulation results verify the feasibility and practicability of this scheme. It thus seems a very promising candidate for constructing high-security network in the near future.
Abstract The possibility for quantum and classical communication to coexist on the same fiber is important for deployment and widespread adoption of quantum key distribution (QKD) and, more generally, a future quantum internet. While coexistence has been demonstrated for different QKD implementations, a comprehensive investigation for measurement-device independent (MDI) QKD—a recently proposed QKD protocol that cannot be broken by quantum hacking that targets vulnerabilities of single-photon detectors—is still missing. Here we experimentally demonstrate that MDI-QKD can operate simultaneously with at least five 10 Gbps bidirectional classical communication channels operating at around 1550 nm wavelength and over 40 km of spooled fiber, and we project communication rates in excess of 10 THz when moving the quantum channel from the third to the second telecommunication window. The similarity of MDI-QKD with quantum repeaters suggests that classical and generalized quantum networks can co-exist on the same fiber infrastructure.