secure communication; quantum communication; device indepenent; quantum key distribution; quantum random number generator
Monteiro F, Verbanis E, Vivoli V Caprara, Martin A, Gisin N, Zbinden H, Thew R T (2017), Heralded amplification of path entangled quantum states, in Quantum Science and Technology
, 2(2), 024008-024008.
Brask Jonatan Bohr, Martin Anthony, Esposito William, Houlmann Raphael, Bowles Joseph, Zbinden Hugo, Brunner Nicolas (2017), Megahertz-Rate Semi-Device-Independent Quantum Random Number Generators Based on Unambiguous State Discrimination, in Physical Review Applied
, 7(5), 054018-054018.
Boaron Alberto, Korzh Boris, Houlmann Raphael, Boso Gianluca, Lim Charles Ci Wen, Martin Anthony, Zbinden Hugo (2016), Detector-device-independent quantum key distribution: Security analysis and fast implementation, in Journal of Applied Physics
, 120(6), 063101-063101.
Guerreiro T., Monteiro F., Martin A., Brask J. B., Vértesi T., Korzh B., Caloz M., Bussières F., Verma V. B., Lita A. E., Mirin R. P., Nam S. W., Marsilli F., Shaw M. D., Gisin N., Brunner N., Zbinden H., Thew R. T. (2016), Demonstration of Einstein-Podolsky-Rosen Steering Using Single-Photon Path Entanglement and Displacement-Based Detection, in Physical Review Letters
, 117(7), 070404-070404.
Verbanis E., Martin A., Rosset D., Lim C. C. W., Thew R. T., Zbinden H. (2016), Resource-Efficient Measurement-Device-Independent Entanglement Witness, in Physical Review Letters
, 116(19), 190501-190501.
Rosset Denis, Martin Anthony, Verbanis Ephanielle, Lim Charles Ci Wen, Thew Rob, Practical measurement-device-independent entanglement quantification, in Physical Review A
In today’s information society, the right to communication privacy and security is of paramount importance to everyone. Recent revelations of the activities of state-actors like the NSA and GCHQ, in spying on global Internet traffic, once again reminds us how fragile these rights can be. In the never-ending cat and mouse game between encryption and cryptanalysis, information theory changed the rules, proving that perfectly secure encryption and authentication is possible, provided two parties secretly share a perfectly random key. Therefore, when it was shown that secure key exchange based on the laws of quantum physics is possible, the outcome of the game appeared decided. Applications such as quantum random number generation (QRNG) and quantum key distribution (QKD) have made enormous progress in the last 30 years and commercial products are now available and operational around the world. However, despite the fact that many theoretical proofs confirmed the security of the different schemes, it quickly became apparent that the experimental realisations are vulnerable due to different kinds of experimental limitations, as is the case for all cryptography. Quantum physics allows us to counter this challenge by also providing the tools for testing and detecting imperfections in hardware. The idea of Device Independent (DI) quantum cryptography is to design protocols whose security does not rely on any detailed assumptions about the internal working of the devices used in the protocol. Devices are seen as ``black boxes'' getting inputs and producing outputs with no assumptions on how the box generates the output, providing it does not violate the laws of quantum physics. This project aims to converge on solutions that bridge the gap between abstract security proofs and the security of real world systems and lay the foundations for improved security for practical quantum communication applications. This will be addressed by: 1)Developing practical implementations of systems that exploit Device Independent concepts for the generation of private and secure randomness for QRNG and its distribution via QKD.2) Improving the efficiency and precision of the components and systems to better characterise potentially imperfect devices such that their limitations can be more reliably taken into account when extracting private and secure keys. Develop novel architectures and protocols that are robust to testable attacks.Both of these approaches rely on precise control and characterisation of quantum systems ranging from single photon sources and detectors to the measurement apparatuses. Device independent schemes provide the most elegant approach, but places extremely challenging limits on system performance and is hard to achieve in practice. However, simpler schemes exist and more are emerging, which can also relax the assumptions on parts of the system. We will be constantly assessing the progress, within the new and exciting field as well as our project, to ensure it successfully achieves its main objectives.