© 2026 Aqora Quantum S.A.S.

Terms Privacy Legal Notice

Acta Physica Sinica

Real-time low-frequency vibration phase drift tracking and auto-compensation in phase-coded quantum key distribution system

Banghong Guo, Lu Yi-Qun, Wang Fa-Qiang, Zhao Feng, Min Hu, Lin Yi-Man, Liao Chang-Jun, Songhao Liu, (1)华南师范大学光子信息技术广东省高校重点实验室，广州 510006; (2)华南师范大学光子信息技术广东省高校重点实验室，广州 510006;广东茂名学院计算机与电子信息学院，茂名 525000

Published Jan 1, 2007• 1 citation

Abstract

Phase drift caused by environment is the main source of quantum bit error rate and instability in the double M-Z interferometer quantum key distribution(QKD) system. The phase drift consists of both high-frequency and low-frequency vibrations, the former, which is due to environment noise, is usually conducted via the atmosphere and can be isolated by technological measures (e.g. using foamed-plastics wrapping or rubber pillow ), the latter comes from building-vibration, which vibrates slowly with a serious impact on M-Z interferometer, with a period of 3±0.32 min (min level). A novel real-time tracking and compensation method for phase drift caused by low-frequency vibration is proposed. With the improved scheme, the QKD system based on double M-Z interferometers can operate stably for 24 hours, and key exchange with an error below 6% over 75 kilometers has been achieved in the lab.

DOI: 10.7498/aps.56.3695

Related papers

Real-Time Phase Tracking Scheme With Mismatched-Basis Data for Phase-Coding Quantum Key Distribution

Dong Wang, Xiaotian Song, Liangjiang Zhou +1 more

Phase drift is an inevitable problem in the practical implementation of phase-coding quantum key distribution (QKD) systems. Conventional active phase tracking and compensation solutions cannot be implemented during the key transmission process, resulting in reduced efficiency of the system. In this paper, we propose a single-photon level real-time phase tracking scheme using only the estimated quantum bit error rate (QBER) and mismatched-basis data to acquire the phase drift parameter instead of a phase scanning process or reference light pulses, without extra hardware or interrupting the transmission of quantum signals. This scheme is applied into a phase-coding QKD system with active phase disturbance and obtains an average QBER of $1.01\%$ with a standard derivation of $0.37\%$ over 50 h of continuous operation. Experimental results show that this scheme enables QKD systems to operate continuously with long-term stability and keep a low level of QBER even with rapid phase drift, suggesting its suitability for practical applications.

IEEE photonics journal•Apr 13, 2020•9 citations

Real-time compensation of phase drift for phase-encoded quantum key distribution systems

Lijun Zhang, Yonggang Wang, Zhen−Qiang Yin +7 more

Phase drift is an inherent problem in phase-encoded quantum key distribution (QKD) systems. The current active phase tracking and compensation solutions cannot satisfy the requirements of a system with nonlinearity in phase modulation. This paper presents a four-phase scanning method, which is based on the quantitative analysis of the quantum bit error rate (QBER) from phase drift and the performance requirements of phase compensation. By obtaining the four interference fringes and adjusting the coding matrix of the system, this method automatically calculates the accurate driving voltages for the phase modulator. The implementation and experimental tests show that the proposed method can compensate phase drift caused by environmental changes and the system’s nonlinearity, and is applicable to large-scale QKD networks.

Chinese Science Bulletin•Jul 11, 2011•21 citations

An effective active phase compensation method for quantum key distribution system

Jindong Wang, Qin Xiao-Juan, Zhengjun Wei +4 more

Quantum key distribution (QKD) system must be robust enough in practical communication. The system performance is notably affected by phase drift. For the fiber-based phase-encoded quantum key distribution system, the Faraday-Michelson QKD scheme can auto-compensate the birefringence of fiber, but phase drift caused by environment variations is still a serious problem in practical operation. In this paper, the major schemes to compensate for the phase drift are analyzed in detail and an “five-phase”effective active phase compensation method is proposed. The comparison with other two major active phase compensation schemes also given. The result shows that this method uses less time to acquire the parameter of phase drift with the same precision and it can be used in phase-encoded QKD systems without introducing additional devices.

Acta Physica Sinica•Jan 1, 2010•2 citations

Self-adpated Quantum Key Distribution All-fiber System

Songhao Liu

By tracking phase drift and distributing key at suitable times,the quantum key distribution based on double M-Z interferometer was performed over a fiber length of 80 km with a quantum bit-error rate of 6%,and it had been working stably for several days.In addition,we demonstrate that the quantum bit-error rate is less than 3.5% within a fiber length of 50 km.Through the local-area network,the key exchange and document transmission were achieved.The scheme applicable to other QKD systems can also improve the stability of interference,which has made progress in the practical application.

Journal of Optoelectronics·laser•Jan 1, 2007•0 citations

Predictive Phase Drift Tracking in Practical Quantum Key Distribution Via LSTM Algorithms

Lijun Zhang, Dongsheng He

Quantum Key Distribution (QKD) systems face challenges due to quantum state drift caused by environmental variations. This paper introduces a phase drift compensation algorithm for QKD systems based on Long Short Term Memory (LSTM) networks. This algorithm only learns, predicts, and compensates for phase drift from intermediate data generated during QKD transmission, without the need for additional data acquisition modules such as environmental monitoring. The experimental results show that the algorithm has high accuracy in tracking phase drift. It performs well on the test set and can accurately match actual scanned data. When implemented in practical GHz QKD systems, this algorithm can increase transmission efficiency by 15 % without reducing the bit error rate. In addition, as the algorithm does not rely on environmental monitoring equipment or high-intensity emission light conditions, it enhances the security of the system and reduces potential security risks.

International Conference on Mobile Internet, Cloud Computing and Information Security (MICCIS)•Apr 11, 2025•0 citations

Practical Real-Time Phase Drift Compensation Scheme for Quantum Communication Systems

Xiaotian Song, Chunsheng Zhang, Dong Pan +4 more

Quantum communication systems are susceptible to various perturbations and drifts arising from the operational environment, with phase drift being a crucial challenge. In this paper, we propose an efficient real-time phase drift compensation scheme in which only existing data from the quantum communication process is used to establish a stable closed-loop control subsystem for phase tracking. This scheme ensures the continuous operation of transmission by tracking and compensating for phase drift in the phase-encoding quantum communication system. The experimental results demonstrate the effectiveness and feasibility of the proposed scheme with an average quantum bit error rate of 1.60% and a standard deviation of 0.0583% for 16 h of continuous operation.

Entropy•Oct 1, 2023•2 citations

Phase drift caused by environment is the main source of quantum bit error rate and instability in the double M-Z interferometer quantum key distribution(QKD) system. The phase drift consists of both high-frequency and low-frequency vibrations, the former, which is due to environment noise, is usually conducted via the atmosphere and can be isolated by technological measures (e.g. using foamed-plastics wrapping or rubber pillow ), the latter comes from building-vibration, which vibrates slowly with a serious impact on M-Z interferometer, with a period of 3±0.32 min (min level). A novel real-time tracking and compensation method for phase drift caused by low-frequency vibration is proposed. With the improved scheme, the QKD system based on double M-Z interferometers can operate stably for 24 hours, and key exchange with an error below 6% over 75 kilometers has been achieved in the lab.

Phase drift is an inevitable problem in the practical implementation of phase-coding quantum key distribution (QKD) systems. Conventional active phase tracking and compensation solutions cannot be implemented during the key transmission process, resulting in reduced efficiency of the system. In this paper, we propose a single-photon level real-time phase tracking scheme using only the estimated quantum bit error rate (QBER) and mismatched-basis data to acquire the phase drift parameter instead of a phase scanning process or reference light pulses, without extra hardware or interrupting the transmission of quantum signals. This scheme is applied into a phase-coding QKD system with active phase disturbance and obtains an average QBER of

1.01\%

with a standard derivation of

0.37\%

over 50 h of continuous operation. Experimental results show that this scheme enables QKD systems to operate continuously with long-term stability and keep a low level of QBER even with rapid phase drift, suggesting its suitability for practical applications.

Phase drift is an inherent problem in phase-encoded quantum key distribution (QKD) systems. The current active phase tracking and compensation solutions cannot satisfy the requirements of a system with nonlinearity in phase modulation. This paper presents a four-phase scanning method, which is based on the quantitative analysis of the quantum bit error rate (QBER) from phase drift and the performance requirements of phase compensation. By obtaining the four interference fringes and adjusting the coding matrix of the system, this method automatically calculates the accurate driving voltages for the phase modulator. The implementation and experimental tests show that the proposed method can compensate phase drift caused by environmental changes and the system’s nonlinearity, and is applicable to large-scale QKD networks.

Quantum key distribution (QKD) system must be robust enough in practical communication. The system performance is notably affected by phase drift. For the fiber-based phase-encoded quantum key distribution system, the Faraday-Michelson QKD scheme can auto-compensate the birefringence of fiber, but phase drift caused by environment variations is still a serious problem in practical operation. In this paper, the major schemes to compensate for the phase drift are analyzed in detail and an “five-phase”effective active phase compensation method is proposed. The comparison with other two major active phase compensation schemes also given. The result shows that this method uses less time to acquire the parameter of phase drift with the same precision and it can be used in phase-encoded QKD systems without introducing additional devices.

By tracking phase drift and distributing key at suitable times,the quantum key distribution based on double M-Z interferometer was performed over a fiber length of 80 km with a quantum bit-error rate of 6%,and it had been working stably for several days.In addition,we demonstrate that the quantum bit-error rate is less than 3.5% within a fiber length of 50 km.Through the local-area network,the key exchange and document transmission were achieved.The scheme applicable to other QKD systems can also improve the stability of interference,which has made progress in the practical application.

Quantum Key Distribution (QKD) systems face challenges due to quantum state drift caused by environmental variations. This paper introduces a phase drift compensation algorithm for QKD systems based on Long Short Term Memory (LSTM) networks. This algorithm only learns, predicts, and compensates for phase drift from intermediate data generated during QKD transmission, without the need for additional data acquisition modules such as environmental monitoring. The experimental results show that the algorithm has high accuracy in tracking phase drift. It performs well on the test set and can accurately match actual scanned data. When implemented in practical GHz QKD systems, this algorithm can increase transmission efficiency by 15 % without reducing the bit error rate. In addition, as the algorithm does not rely on environmental monitoring equipment or high-intensity emission light conditions, it enhances the security of the system and reduces potential security risks.

Quantum communication systems are susceptible to various perturbations and drifts arising from the operational environment, with phase drift being a crucial challenge. In this paper, we propose an efficient real-time phase drift compensation scheme in which only existing data from the quantum communication process is used to establish a stable closed-loop control subsystem for phase tracking. This scheme ensures the continuous operation of transmission by tracking and compensating for phase drift in the phase-encoding quantum communication system. The experimental results demonstrate the effectiveness and feasibility of the proposed scheme with an average quantum bit error rate of 1.60% and a standard deviation of 0.0583% for 16 h of continuous operation.