Id Quantique Sa

Matthieu Legré

Grégoire Ribordy

Damien Stucki

Bruno Huttner

Free-Space key distribution method comprising exchanging information between an emitter () and a receiver () based on the physical layer wiretap channel model, comprising the steps of randomly preparing (), at the emitter (), one qubit encoded with one of two possible non-identical quantum states, sending () the encoded qubit to the receiver () through a physical layer quantum-enhanced wiretap channel (), such that an eavesdropper () tapping said channel is provided with partial information about the said states only, detecting and measuring () the received quantum states, key sifting () between the emitter and the receiver through a classical channel, calculating () an amount of information available to any eavesdropper () based on the detected and received quantum states.

Apparatus and method for quantum enhanced physical layer security

An apparatus for enhancing secret key rate exchange over quantum channel in QKD systems includes an emitter system with a quantum emitter and a receiver system with a quantum receiver, wherein both systems are connected by a quantum channel and a service communication channel. User interfaces within the systems allow to define a first quantum channel loss budget based on the distance to be covered between the quantum emitter and the quantum receiver and the infrastructure properties of the quantum channel as well as a second quantum channel loss budget associated to the loss within the realm of the emitter system. The emitter system is adapted to define the optimal mean number of photons of coherent states to be emitted based on the first and the second quantum channel loss budgets.

Apparatus and method for enhancing secret key rate exchange over quantum channel in quantum key distribution systems

The invention relates to a QKD System Active combiner () adapted to be installed in a QKD apparatus, said QKD apparatus comprising an emitter (), a receiver () and QKD systems (), wherein the emitter () is adapted to send communication signals to the receiver () through the QKD System Active combiner (), characterized in that the QKD System Active combiner () comprises an active attenuation system comprising a processing unit () adapted to automatically control at least one variable optical attenuator () through a control channel () in order to control an attenuation of a signal to be sent to the receiver, and a detector/monitor () adapted to monitor the intensity of the signal downstream the attenuation, and wherein the processing unit is adapted to control the variable optical attenuator () based on a QBER information or an intensity of a signal received by the receiver, sent by the QKD systems () through a classical channel ().

Apparatus and method for direct quantum cryptography system implementation over WDM telecommunication network

An apparatus and method for revealing both attack attempts performed on the single-photon detector(s) of a quantum cryptography system and Trojan horse attack attempts performed on quantum cryptography apparatus containing at least one single photon detector. The attacks detection relies on both the random modification of the setting parameters of the said single-photon detector(s) and the comparison of the measured detection probability values for each setting parameter with the expected detection probability values. The modified parameter of the single-photon detector can be its efficiency or its timing of activation for example.

Apparatus and method for the detection of attacks taking control of the single photon detectors of a quantum cryptography apparatus by randomly changing their efficiency

Growing community of inventors

Veigy-Foncenex, France

Matthieu Legré