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Experimental multiuser secure quantum communications

Jan Bogdanski

Published Jan 1, 2009• 0 citations
OpenAlex

Abstract

We are currently experiencing a rapid development of quantum information, a new branch of science, being an interdisciplinary of quantum physics, information theory, telecommunications, computer science, and many others. This new science branch was born in the middle of the eighties, developed rapidly during the nineties, and in the current decade has brought a technological breakthrough in creating secure quantum key distribution (QKD), quantum secret sharing, and exciting promises in diverse technological fields. Recent QKD experiments have achieved high rate QKD at 200 km distance in optical fiber. Significant QKD results have also been achieved in free-space. Due to the rapid broadband access deployment in many industrialized countries and the standing increasing transmission security treats, the natural development awaiting quantum communications, being a part of quantum information, is its migration into commercial switched telecom networks. Such a migration concerns both multiuser quantum key distribution and multiparty quantum secret sharing that have been the main goal of my PhD studies. They are also the main concern of the thesis. Our research efforts in multiuser QKD has led to a development of the five-user setup for transmissions over switched fiber networks in a star and in a tree configuration. We have achieved longer secure quantum information distances and implemented more nodes than other multi-user QKD experiments. The measurements have shown feasibility of multiuser QKD over switched fiber networks, using standard fiber telecom components. Since circular architecture networks are important parts of both intranets and the Internet, Sagnac QKD has also been a subject of our research efforts. The published experiments in this area have been very few and results were not encouraging, mainly due to the single mode fiber (SMF) birefringence. Our research has led to a development of a computer controlled birefringence compensation in Sagnac that open the door to both classical and quantum Sagnac applications. On the quantum secret sharing side, we have achieved the first quantum secret sharing experiment over telecom fiber in a five-party implementation using the "plug & play" setup and in a four-party implementation using Sagnac configuration. The setup measurements have shown feasibility and scalability of multiparty quantum communication over commercial telecom fiber networks.

Related papers

Sagnac quantum key distribution and secret sharing

Jan Bogdanski, Johan Ahrens, Mohamed Bourennane

We present the first Sagnac quantum secret sharing (in three- and four-party implementations) as well as Sagnac two-user quantum key distribution (QKD) over 1550 nm single mode fiber (SMF) networks, using the BB84- protocol with phase encoding. The secret sharing experiment has implemented a single qubit protocol, which allows for a practical secret sharing implementation over fiber telecom channels and in free-space. The previous quantum secret sharing proposals were based on multiparticle entangled states, not scalable and diffcult in the experimental implementations. Our experimental data show stable, in regards to birefringence drift, quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km with the quantum bit error rates (QBER) of 3.0-3.7 % for the mean photon number μ = 0.1. In the QKD experiment we have achieved the total Sagnac transmission loop distances of 100-150 km with quantum bit error rates (QBER) of 5.84-9.79 % for μ = 0.1. The distances were much longer and rates much higher than in any other published Sagnac QKD experiments. The stability of quantum transmission in both secret sharing and QKD experiments has been achieved thanks to our new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator. The measurement results have showed feasibility of quantum secret sharing and QKD over telecom fiber networks in Sagnac confi;guration, using standard fiber telecom components. Our birefringence compensation in SMF Sagnac open the door to other Sagnac-based applications over SMF links such as precise optical sensing, dispersion characteristics of optical fibers, acoustic and strain sensing, and generally sensing of any time varying phenomenon.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Dec 2, 2008•3 citations

Sagnac secret sharing over telecom fiber networks

Jan Bogdanski, Johan Ahrens, Mohamed Bourennane

We report the first Sagnac quantum secret sharing (in three-and four-party implementations) over 1550 nm single mode fiber (SMF) networks, using a single qubit protocol with phase encoding. Our secret sharing experiment has been based on a single qubit protocol, which has opened the door to practical secret sharing implementation over fiber telecom channels and in free-space. The previous quantum secret sharing proposals were based on multiparticle entangled states, difficult in the practical implementation and not scalable. Our experimental data in the three-party implementation show stable (in regards to birefringence drift) quantum secret sharing transmissions at the total Sagnac transmission loop distances of 55-75 km with the quantum bit error rates (QBER) of 2.3-2.4% for the mean photon number micro?= 0.1 and 1.7-2.1% for micro= 0.3. In the four-party case we have achieved quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km with the quantum bit error rates (QBER) of 3.0-3.7% for the mean photon number micro= 0.1 and 1.8-3.0% for micro?= 0.3. The stability of quantum transmission has been achieved thanks to our new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator. The measurement results have showed feasibility of quantum secret sharing over telecom fiber networks in Sagnac configuration, using standard fiber telecom components.

Optics Express•Jan 15, 2009•13 citations

Secure multiparty quantum communication over telecom fiber networks

Jan Bogdanski, Johan Ahrens, Nima Rafiei +2 more

The paper reports on the first fiber quantum secret sharing experiment in three, four, and five-party implementations in the plug & play and Sagnac interferometer setups using single photons with phase encoding. A plug & play setup a secure secret sharing transmission distance of 66:1 km has been achieved for three-party with quantum bit error rate (QBER) of 7.1%; 40:5 km for four-party with QBER of 6:6%; and 6:7 km with QBER of 2:7%, suitable for local area network (LAN) applications, for five-party. In Sagnac interferometric setup, our experimental data in the three-party implementation show stable (in regards to birefringence drift) quantum secret sharing transmissions at the total Sagnac transmission loop distances of 55-75 km with the quantum bit error rates (QBER) of 2.3-2.4% for the mean photon number mu = 0.1 and 1.7-2.1% for mu = 0.3. In the four-party case a quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km has been achieved with the quantum bit error rates (QBER) of 3.0-3.7% for the mean photon number mu = 0.1 and 1.8- 3.0% for mu = 0.3. The stability of quantum transmission has been achieved due to the new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2009•1 citation

Experimental Quantum Communication based on Sagnac Interferometers

Xiaoqing Zhong

Quantum communication uses quantum states to transmit information. The core of quantum communication rests on distinctive quantum properties, such as quantum superposition and entanglement, allowing communication tasks to be achieved more efficiently or securely than classical communication. Over the past few decades, quantum communication theory has gone through a spurt of growth and is now encompassing various branches. While theoretical framework of quantum communication has been firmly established, there is a big gap between theory and practice of quantum communication. The practical challenges set limitations to implementations of many quantum communication protocols. In this thesis, I present my research effort in exploring viable solutions to accelerate the pace of experimental development of quantum communication. The scope of quantum communication is rather broad. My research in this thesis is restricted to two branches, namely quantum fingerprinting (QF) and quantum key distribution (QKD). In the first part of the thesis, I present our proposed QF protocol which, with the use of wavelength division multiplexing, can shorten the communication time and communication complexity of an existing QF protocol. An experimental demonstration with 6 wavelength channels is also presented, which has experimentally verified the advantage of our proposed protocol in communication complexity. I present my experimental studies on QKD in the remainder of this thesis, focusing on twin-field-QKD (TF-QKD), which can practically overcome the rate-loss limit of conventional point-to-point QKD protocols. My exploration of TF-QKD is composed of three stages. a) I performed one of the first four experimental implementations of TF-QKD. A Sagnac-interferometer-based configuration was used to overcome the main practical challenge (long-term phase stability). b) Based on the same configuration, I investigated the implementation of TF-QKD over asymmetric optical channels, providing an optimal compensation strategy to improve the performance of TF-QKD in practical situations. c) I extended my study on TF-QKD into building the first TF-QKD network, an essential step towards the development of a global quantum internet. In summary, in this thesis, I present feasible solutions with accessible techniques, such as multiplexing and Sagnac interferometer, to overcome practical challenges in QF and QKD, bringing these protocols closer to real-world applications.

•Jun 1, 2022•0 citations

Five-user QKD over switched fiber networks

Jan Bogdanski, Nima Rafiei, Mohamed Bourennane

Unconditionally secure multiuser quantum key distribution (QKD) over long distance switched telecom fiber networks will have a revolutionary impact on people's, companies', and governmental exchange of confidential information. We report five-user QKD over switched fiber networks in both star and tree configurations, using the BB84-protocol with phase encoding. Both setups implement polarization insensitive phase modulators, necessary for birefringent single mode fiber networks. In both configurations, for the mean photon number μ=0.1, we have achieved raw rates between 50Hz and 300Hz at distances between 25km to 50km with quantum bit error rates between 1.24% to 5.56%. The measurements have showed feasibility of multiuser QKD over switched telecom fiber networks, using standard fiber telecom components.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 5, 2008•0 citations

High-dimensional and multiplexed schemes for fiber-based quantum key distribution protocols.

Beatrice Da Lio

Quantum key distribution protocols are easily the most advanced quantum information technology up to date, driving the whole field of quantum communications towards actual systems implementations and flourishing theoretical advances and experimental demonstrations. Exploiting the consolidated telecommunications industry knowledge, optimized equipment and already existing broad infrastructure, fiber-based quantum key distribution schemes are in particular a promising direction in which the scientific research efforts are addressed, for the final goal of building a quantum network. However, three main challenges are still preventing the large-scale industrial deployment of fiber-based quantum key distribution schemes: the limited achievable secret key generation rate, when compared to those reached by classical communications; the bounded propagation distances, due to intrinsic channel losses; and the struggle of the integration with classical data rates, which are additional sources of noise from the point of view of a quantum channel. During my Ph.D., we have focused on two of these problems, proposing new efficient designs for fiber-based high-dimensional protocols and space division multiplexing schemes to increase the secret key rate of quantum systems, and investigating the optimization of wavelength multiplexing setups for the integration with classical communications.

•Jan 1, 2020•0 citations
We are currently experiencing a rapid development of quantum information, a new branch of science, being an interdisciplinary of quantum physics, information theory, telecommunications, computer science, and many others. This new science branch was born in the middle of the eighties, developed rapidly during the nineties, and in the current decade has brought a technological breakthrough in creating secure quantum key distribution (QKD), quantum secret sharing, and exciting promises in diverse technological fields. Recent QKD experiments have achieved high rate QKD at 200 km distance in optical fiber. Significant QKD results have also been achieved in free-space. Due to the rapid broadband access deployment in many industrialized countries and the standing increasing transmission security treats, the natural development awaiting quantum communications, being a part of quantum information, is its migration into commercial switched telecom networks. Such a migration concerns both multiuser quantum key distribution and multiparty quantum secret sharing that have been the main goal of my PhD studies. They are also the main concern of the thesis. Our research efforts in multiuser QKD has led to a development of the five-user setup for transmissions over switched fiber networks in a star and in a tree configuration. We have achieved longer secure quantum information distances and implemented more nodes than other multi-user QKD experiments. The measurements have shown feasibility of multiuser QKD over switched fiber networks, using standard fiber telecom components. Since circular architecture networks are important parts of both intranets and the Internet, Sagnac QKD has also been a subject of our research efforts. The published experiments in this area have been very few and results were not encouraging, mainly due to the single mode fiber (SMF) birefringence. Our research has led to a development of a computer controlled birefringence compensation in Sagnac that open the door to both classical and quantum Sagnac applications. On the quantum secret sharing side, we have achieved the first quantum secret sharing experiment over telecom fiber in a five-party implementation using the "plug & play" setup and in a four-party implementation using Sagnac configuration. The setup measurements have shown feasibility and scalability of multiparty quantum communication over commercial telecom fiber networks.
We present the first Sagnac quantum secret sharing (in three- and four-party implementations) as well as Sagnac two-user quantum key distribution (QKD) over 1550 nm single mode fiber (SMF) networks, using the BB84- protocol with phase encoding. The secret sharing experiment has implemented a single qubit protocol, which allows for a practical secret sharing implementation over fiber telecom channels and in free-space. The previous quantum secret sharing proposals were based on multiparticle entangled states, not scalable and diffcult in the experimental implementations. Our experimental data show stable, in regards to birefringence drift, quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km with the quantum bit error rates (QBER) of 3.0-3.7 % for the mean photon number μ = 0.1. In the QKD experiment we have achieved the total Sagnac transmission loop distances of 100-150 km with quantum bit error rates (QBER) of 5.84-9.79 % for μ = 0.1. The distances were much longer and rates much higher than in any other published Sagnac QKD experiments. The stability of quantum transmission in both secret sharing and QKD experiments has been achieved thanks to our new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator. The measurement results have showed feasibility of quantum secret sharing and QKD over telecom fiber networks in Sagnac confi;guration, using standard fiber telecom components. Our birefringence compensation in SMF Sagnac open the door to other Sagnac-based applications over SMF links such as precise optical sensing, dispersion characteristics of optical fibers, acoustic and strain sensing, and generally sensing of any time varying phenomenon.
We report the first Sagnac quantum secret sharing (in three-and four-party implementations) over 1550 nm single mode fiber (SMF) networks, using a single qubit protocol with phase encoding. Our secret sharing experiment has been based on a single qubit protocol, which has opened the door to practical secret sharing implementation over fiber telecom channels and in free-space. The previous quantum secret sharing proposals were based on multiparticle entangled states, difficult in the practical implementation and not scalable. Our experimental data in the three-party implementation show stable (in regards to birefringence drift) quantum secret sharing transmissions at the total Sagnac transmission loop distances of 55-75 km with the quantum bit error rates (QBER) of 2.3-2.4% for the mean photon number micro?= 0.1 and 1.7-2.1% for micro= 0.3. In the four-party case we have achieved quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km with the quantum bit error rates (QBER) of 3.0-3.7% for the mean photon number micro= 0.1 and 1.8-3.0% for micro?= 0.3. The stability of quantum transmission has been achieved thanks to our new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator. The measurement results have showed feasibility of quantum secret sharing over telecom fiber networks in Sagnac configuration, using standard fiber telecom components.
The paper reports on the first fiber quantum secret sharing experiment in three, four, and five-party implementations in the plug & play and Sagnac interferometer setups using single photons with phase encoding. A plug & play setup a secure secret sharing transmission distance of 66:1 km has been achieved for three-party with quantum bit error rate (QBER) of 7.1%; 40:5 km for four-party with QBER of 6:6%; and 6:7 km with QBER of 2:7%, suitable for local area network (LAN) applications, for five-party. In Sagnac interferometric setup, our experimental data in the three-party implementation show stable (in regards to birefringence drift) quantum secret sharing transmissions at the total Sagnac transmission loop distances of 55-75 km with the quantum bit error rates (QBER) of 2.3-2.4% for the mean photon number mu = 0.1 and 1.7-2.1% for mu = 0.3. In the four-party case a quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km has been achieved with the quantum bit error rates (QBER) of 3.0-3.7% for the mean photon number mu = 0.1 and 1.8- 3.0% for mu = 0.3. The stability of quantum transmission has been achieved due to the new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator.
Quantum communication uses quantum states to transmit information. The core of quantum communication rests on distinctive quantum properties, such as quantum superposition and entanglement, allowing communication tasks to be achieved more efficiently or securely than classical communication. Over the past few decades, quantum communication theory has gone through a spurt of growth and is now encompassing various branches. While theoretical framework of quantum communication has been firmly established, there is a big gap between theory and practice of quantum communication. The practical challenges set limitations to implementations of many quantum communication protocols. In this thesis, I present my research effort in exploring viable solutions to accelerate the pace of experimental development of quantum communication. The scope of quantum communication is rather broad. My research in this thesis is restricted to two branches, namely quantum fingerprinting (QF) and quantum key distribution (QKD). In the first part of the thesis, I present our proposed QF protocol which, with the use of wavelength division multiplexing, can shorten the communication time and communication complexity of an existing QF protocol. An experimental demonstration with 6 wavelength channels is also presented, which has experimentally verified the advantage of our proposed protocol in communication complexity. I present my experimental studies on QKD in the remainder of this thesis, focusing on twin-field-QKD (TF-QKD), which can practically overcome the rate-loss limit of conventional point-to-point QKD protocols. My exploration of TF-QKD is composed of three stages. a) I performed one of the first four experimental implementations of TF-QKD. A Sagnac-interferometer-based configuration was used to overcome the main practical challenge (long-term phase stability). b) Based on the same configuration, I investigated the implementation of TF-QKD over asymmetric optical channels, providing an optimal compensation strategy to improve the performance of TF-QKD in practical situations. c) I extended my study on TF-QKD into building the first TF-QKD network, an essential step towards the development of a global quantum internet. In summary, in this thesis, I present feasible solutions with accessible techniques, such as multiplexing and Sagnac interferometer, to overcome practical challenges in QF and QKD, bringing these protocols closer to real-world applications.
Unconditionally secure multiuser quantum key distribution (QKD) over long distance switched telecom fiber networks will have a revolutionary impact on people's, companies', and governmental exchange of confidential information. We report five-user QKD over switched fiber networks in both star and tree configurations, using the BB84-protocol with phase encoding. Both setups implement polarization insensitive phase modulators, necessary for birefringent single mode fiber networks. In both configurations, for the mean photon number μ=0.1, we have achieved raw rates between 50Hz and 300Hz at distances between 25km to 50km with quantum bit error rates between 1.24% to 5.56%. The measurements have showed feasibility of multiuser QKD over switched telecom fiber networks, using standard fiber telecom components.
Quantum key distribution protocols are easily the most advanced quantum information technology up to date, driving the whole field of quantum communications towards actual systems implementations and flourishing theoretical advances and experimental demonstrations. Exploiting the consolidated telecommunications industry knowledge, optimized equipment and already existing broad infrastructure, fiber-based quantum key distribution schemes are in particular a promising direction in which the scientific research efforts are addressed, for the final goal of building a quantum network. However, three main challenges are still preventing the large-scale industrial deployment of fiber-based quantum key distribution schemes: the limited achievable secret key generation rate, when compared to those reached by classical communications; the bounded propagation distances, due to intrinsic channel losses; and the struggle of the integration with classical data rates, which are additional sources of noise from the point of view of a quantum channel. During my Ph.D., we have focused on two of these problems, proposing new efficient designs for fiber-based high-dimensional protocols and space division multiplexing schemes to increase the secret key rate of quantum systems, and investigating the optimization of wavelength multiplexing setups for the integration with classical communications.