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Quantum Electronics and Laser Science Conference

Quantum cryptography without optical fibers

J. D. Franson, B. C. Jacobs

Published Jun 7, 1996• 1 citation
OpenAlex

Abstract

Summary form only given. Current limitations on the range of quantum cryptography systems using optical fibers could be eliminated if it were possible to transmit and receive single photons between a ground station and a satellite, and between two satellites, which would allow the operation of a global network for secure communications. We are currently investigating the feasibility of such systems, with the initial goal of demonstrating secure communications between two ground stations in open air during daylight hours.

Related papers

Quantum cryptography in free space

B. C. Jacobs, J. D. Franson

The range of quantum cryptography systems using optical fibers is limited to roughly 30 km because amplifiers cannot be used. A fully operational system for quantum cryptography based on the transmission of single photons in free space under daylight conditions has been demonstrated. The feasibility of a global system for quantum cryptography based on a network of ground stations and satellites is discussed.

Optics Letters•Nov 15, 1996•121 citations

Quantum communications

J. D. Franson

Quantum mechanics allows a number of communications protocols that would not be possible classically, including provably-secure messages (quantum cryptography), increased channel capacity, and the ability to transmit an unknown quantum state (quantum teleportation). This tutorial will provide an introductory description of what appear to be the most promising applications of quantum communications, including quantum cryptography and quantum repeaters. The most commonly-used methods for quantum cryptography will be described, including the advantages and disadvantages of each in practical applications. The maximum range of current quantum cryptography systems is limited by the fact that optical amplifiers would destroy the quantum coherence of single photons and cannot be used in these kinds of systems. One potential solution to this problem is the transmission of single photons in free space, which would allow a global system for quantum cryptography based on a network of satellites and ground stations. Free-space quantum cryptography systems of that kind have now been demonstrated over relatively short distances. The range of quantum cryptography systems in optical fibers can also be extended using quantum repeaters that make use of entanglement purification and quantum teleportation. These same techniques could also be used to implement a “quantum Internet” for the transmission of qubits from one quantum computer to another. The practical challenges that will have to be met in order to implement quantum repeaters and quantum teleportation over large distances will be discussed.

Optical Fiber Communication Conference•Jan 1, 2001•1 citation

Quantum cryptography for secure satellite communications

Richard Hughes, W. T. Buttler, Paul G. Kwiat +4 more

Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and recent results from our experimental free-space system with which we have demonstrated the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit for encrypting the uplinked command path and downlinked data path; or to distribute keys between widely-separated ground stations with a satellite relay, enabling encrypted communications over even inter-continental distances. We present a feasibility analysis of surface-to-satellite quantum key generation.

IEEE Aerospace Conference (AERO)•Nov 7, 2002•37 citations

Practical quantum cryptography for secure free-space communications

Richard Hughes, W. T. Buttler, Paul G. Kwiat +4 more

Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and the most recent results from our experimental free-space system with which we have demonstrated for the first time the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit. We present a feasibility analysis of surface-to-satellite quantum key generation.

arXiv:quant-ph/9905009•May 4, 1999•20 citations

Development of the polarization tracking scheme for free-space quantum cryptography

Morio Toyoshima, Yoshihisa Takayama, Hiroo Kunimori +3 more

Quantum cryptography is a new technique for transmitting quantum information. The information is securely transmitted due to the laws of physics. In such systems, the vehicle that transfers quantum information is a single photon. The problem with using photons is that the transmission distance is limited by the absorption of the photons by the optical fiber along which they pass. The maximum demonstrated range so far is approximately 100 km. Using free-space quantum cryptography between a ground station and a satellite is a possible way of sending quantum information farther than is possible with optical fibers. This is because there is no birefringence effect in the atmosphere. However, there is a complication in that the directions of the polarization basis between the transmitter and the receiver must coincide with each other. This polarization changes because the mobile terminals for free-space transmission continuously change their attitudes. If the transmission protocol is based on polarization, it is necessary to compensate for the change in attitude between the mobile terminals. We are developing a scheme to track the polarization basis between the transceivers. The preliminary result is presented.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Apr 3, 2008•4 citations

QUANTUM CRYPTOGRAPHY: PRINCIPLES, PROBLEMS, AND PROSPECTS

Ілля Геннадійович Калюжний

Quantum cryptography is a relatively new but promising method for secure data transmission. Today it is believed that it can ensure the absolute secrecy of data, resulting from the principles of quantum physics, on which it is based, namely the uncertainty principle of quantum Heisenberg. According to this principle cannot measure any aspect of photons without distorting thus irrevocably different option. That is the recipient of a message knows when attempting invasion in this necessarily knows.To create a quantum communication channel often use fiber optic lines or open space in which carriers serve single photons or pairs of entangled photons are often used.Three tasks facing cryptography are:1. Ensuring the confidentiality of messages sent via open communication channels.2. Authentication messages that confirm the validity of the information received and sent.3. Installing intrusion in fact, if it took place.Given the importance of information security, quantum cryptography technology will soon be available not only banks or large corporations but also individuals. Leading IT companies are in search of optimum circuit solutions that would produce industrial equipment for the transmission of confidential information available for mass use. The main obstacles for implementation of quantum cryptography methods are short distances, which can transmit information with modern facilities, high cost and cumbersome equipment. To solve these problems prompted the idea of creating a hybrid air-fiber system using satellite communications is proposed. The use of artificial satellites for the transmission of photons through the air opens the possibility of secret key clients in any part of the Earth and even beyond.It is also appropriate to review the possibility of using existing telecommunication and electrical networks for the transmission of quantum keys. The ideas p presented in the paper, open new space for scientific experiments.

Information systems mechanics and control•Nov 7, 2015•1 citation
Summary form only given. Current limitations on the range of quantum cryptography systems using optical fibers could be eliminated if it were possible to transmit and receive single photons between a ground station and a satellite, and between two satellites, which would allow the operation of a global network for secure communications. We are currently investigating the feasibility of such systems, with the initial goal of demonstrating secure communications between two ground stations in open air during daylight hours.
Quantum mechanics allows a number of communications protocols that would not be possible classically, including provably-secure messages (quantum cryptography), increased channel capacity, and the ability to transmit an unknown quantum state (quantum teleportation). This tutorial will provide an introductory description of what appear to be the most promising applications of quantum communications, including quantum cryptography and quantum repeaters. The most commonly-used methods for quantum cryptography will be described, including the advantages and disadvantages of each in practical applications. The maximum range of current quantum cryptography systems is limited by the fact that optical amplifiers would destroy the quantum coherence of single photons and cannot be used in these kinds of systems. One potential solution to this problem is the transmission of single photons in free space, which would allow a global system for quantum cryptography based on a network of satellites and ground stations. Free-space quantum cryptography systems of that kind have now been demonstrated over relatively short distances. The range of quantum cryptography systems in optical fibers can also be extended using quantum repeaters that make use of entanglement purification and quantum teleportation. These same techniques could also be used to implement a “quantum Internet” for the transmission of qubits from one quantum computer to another. The practical challenges that will have to be met in order to implement quantum repeaters and quantum teleportation over large distances will be discussed.
Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and recent results from our experimental free-space system with which we have demonstrated the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit for encrypting the uplinked command path and downlinked data path; or to distribute keys between widely-separated ground stations with a satellite relay, enabling encrypted communications over even inter-continental distances. We present a feasibility analysis of surface-to-satellite quantum key generation.
Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and the most recent results from our experimental free-space system with which we have demonstrated for the first time the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit. We present a feasibility analysis of surface-to-satellite quantum key generation.
Quantum cryptography is a new technique for transmitting quantum information. The information is securely transmitted due to the laws of physics. In such systems, the vehicle that transfers quantum information is a single photon. The problem with using photons is that the transmission distance is limited by the absorption of the photons by the optical fiber along which they pass. The maximum demonstrated range so far is approximately 100 km. Using free-space quantum cryptography between a ground station and a satellite is a possible way of sending quantum information farther than is possible with optical fibers. This is because there is no birefringence effect in the atmosphere. However, there is a complication in that the directions of the polarization basis between the transmitter and the receiver must coincide with each other. This polarization changes because the mobile terminals for free-space transmission continuously change their attitudes. If the transmission protocol is based on polarization, it is necessary to compensate for the change in attitude between the mobile terminals. We are developing a scheme to track the polarization basis between the transceivers. The preliminary result is presented.
Quantum cryptography is a relatively new but promising method for secure data transmission. Today it is believed that it can ensure the absolute secrecy of data, resulting from the principles of quantum physics, on which it is based, namely the uncertainty principle of quantum Heisenberg. According to this principle cannot measure any aspect of photons without distorting thus irrevocably different option. That is the recipient of a message knows when attempting invasion in this necessarily knows.To create a quantum communication channel often use fiber optic lines or open space in which carriers serve single photons or pairs of entangled photons are often used.Three tasks facing cryptography are:1. Ensuring the confidentiality of messages sent via open communication channels.2. Authentication messages that confirm the validity of the information received and sent.3. Installing intrusion in fact, if it took place.Given the importance of information security, quantum cryptography technology will soon be available not only banks or large corporations but also individuals. Leading IT companies are in search of optimum circuit solutions that would produce industrial equipment for the transmission of confidential information available for mass use. The main obstacles for implementation of quantum cryptography methods are short distances, which can transmit information with modern facilities, high cost and cumbersome equipment. To solve these problems prompted the idea of creating a hybrid air-fiber system using satellite communications is proposed. The use of artificial satellites for the transmission of photons through the air opens the possibility of secret key clients in any part of the Earth and even beyond.It is also appropriate to review the possibility of using existing telecommunication and electrical networks for the transmission of quantum keys. The ideas p presented in the paper, open new space for scientific experiments.