The present invention relates to a Quantum Key Distribution Network comprising a Quantum Key Distribution layer comprising a plurality of pairs of emitters and receivers and a plurality of Core Nodes and Edge Nodes and a Key Management Layer adapted to exclusively receive XORed-keys from the Core Nodes, mix said XORed-keys from the Core Nodes, and send said mixed XORed-keys to the Edge Nodes of the QKD layer, in order to generate a shared key between said Edge Nodes.
The invention relates to a QKD Communication intermediary component adapted to be placed between two remote QKD modules that are adapted to respectively send and/or receive quantum states to said QKD Communication intermediary component. Said QKD Communication intermediary component comprising: a post-processing unit, a synchronizing processing unit, at least two independent optical modules being adapted to prepare or measure the quantum states, which comprise raw key material to be exchanged with the two remote QKD modules, wherein the at least two independent optical modules send the information corresponding to the prepared and measured quantum states to the synchronizing processing unit, characterized in that the synchronizing processing unit is arranged to operate simultaneously with the first and second remote optical modules and the at least two independent optical modules so as to process said information received from the at least two independent optical modules and comprises at least one memory adapted to temporarily store data coming from one of the at least two optical modules until the data from the other optical module(s) is input in the synchronizing processing unit and is adapted to erase the said at least one memory in the timescale of two consecutive detection events after outputting necessary information to enable a key establishment at the two remote QKD modules.
The present invention relates to an Entropy measurement method comprising the steps of a start-up phase comprising powering on the entropy source unity, a signal emitting step comprising emitting a quantum signal characterized by an overall noise made of classical noise and quantum noise, a noise measurement step comprising measuring the statistics of overall noise through active pixels upon illumination and the statistics of classical noise through non-illuminated pixels, a quantum noise calculation step comprising calculating the quantum noise based on the difference between the overall noise and the classical noise, an health check step comprising comparing the resulting quantum noise to an expected quantum noise and/or a predetermined threshold and a health control step controlling the entropy source unit based on the result of the entropy estimation step.
The present invention relates to a RNG Chip testing method comprising a test start-up phase starting a Final Test phase, a data collection step wherein frames of bit sequences having a length of 1024 KB, preferably 512 KB generated by the RNG chip are collected, a uniformity determining step comprising calculating the uniformity of the bit sequence according the following formula : formula (I), a comparison step where the determined uniformity is compared to a predetermined threshold, and a judging step judging whether the chip has passed or failed the test based on the result of the comparison step.
The present invention relates to a lidar (1000) comprising an emitter (1100) and a receiver (1200), wherein the receiver (1200) comprises a discrete amplification photon detector (1210), wherein the receiver (1200) comprises a discriminator (1220), wherein the discriminator (1220) has an input connected to an output signal of the discrete amplification photon detector (1210), and wherein the discriminator (1220) is configured to output a signal indicating that the output signal of the discrete amplification photon detector (1210) is higher than a predetermined threshold.
G01S 7/00 - RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - Details of systems according to groups , ,
G01S 17/89 - Lidar systems, specially adapted for specific applications for mapping or imaging
6.
DEVICE AND SYSTEM FOR SINGLE PHOTON DETECTION USING A PLURALITY OF SUPERCONDUCTING DETECTION MEANS CONNECTED IN PARALLEL
The present invention concerns a for single photon detection comprising at least two superconducting detection means (1) as well as a bias current source (2), a filter element (3) and a readout circuit (4), wherein each superconducting detection means (1) forms a detection area adapted for absorption of incident photons and is connected in parallel, each superconducting detection means (1) being maintained at a temperature below its critical temperature (TC) and provided with an electrical bias current (IB) situated close to and below its critical current (IC) such as to normally be maintained in a non-resistive superconducting state, and being adapted to transition, at photon absorption, from said non-resistive superconducting state to a resistive state due to an increase in current density within the superconducting detection means (1) above the critical current (IC), said readout circuit (4) being adapted to sense a voltage change corresponding to said transition of the superconducting detection means (1) into its resistive state, such as to allow to create an event signal for each absorption of an incident photon by any of said superconducting detection means (1). The device distinguishes itself by the fact that it further comprises at least one current re-distribution means (5) adapted for at least partly redistributing current arising after absorption of incident photons by any of said superconducting detection means (1) into said current re-distribution means (5), such as to avoid any of the superconducting detection means (1) not having absorbed an incident photon of suffering an increase in current density above its critical current (IC). The present invention also concerns a system for single photon detection comprising at least two such devices.
G01J 5/20 - Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices
H01L 39/00 - Devices using superconductivity or hyperconductivity; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof
G01J 1/42 - Photometry, e.g. photographic exposure meter using electric radiation detectors
H01L 39/16 - Devices switchable between superconductive and normal states
H01L 39/10 - Devices using superconductivity or hyperconductivity; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof - Details characterised by the means for switching
The present invention relates to a quantum key distribution method 2000 for distributing a secret key over a quantum communication channel between a transmitter and a receiver, the method comprising the steps of: synchronizing S2100 a clock between the transmitter and the receiver, distributing S2200 the secret key from the transmitter to the receiver, wherein the synchronizing step S2100 comprises: a first transmitting step S2120 for transmitting a N-th bit of the clock from the transmitter to the receiver, a second transmitting step S2130 for transmitting acknowledgement of reception of the N-th bit from the receiver to the transmitter, a first checking step S2140 for checking if the N-th bit is a most significant bit of the clock, and an incrementing step S2150 for incrementing the value of N if the first checking step S2140 indicates that the N-th bit is not the most significant bit of the clock.
A quantum key distribution (QKD) system comprising: an emitter (110) adapted to generate a QKD free-space signal, a transmitter station (220) adapted to receive the free-space signal from the emitter (110), and a remote QKD receiving station (250) supporting a QKD receiver (160) located at a different location than the transmitter station, wherein the transmitter station is adapted to receive said free space signal from the emitter and to forward said signal through a fiber link (400) to the QKD receiver (160) in said remote QKD receiving station (250).
The present relates to a QKD receiver (300-700) comprising an optical system (110), at least two detectors (120, 130, 220 230), a processing unit (140) and a buffer (170, 270), characterized in that the buffer (170, 270) is adapted to temporarily store an information that the receiver (300-700) sends back to the emitter via a service channel once one of the detectors receives quantum data,, so as to introduce a delay time into the communication process to assure that the communication restarts only after a deadtime of all the detectors (120, 130) has lapsed.
The present invention relates to a receiver (2200) for recognizing blinding attacks in a quantum encrypted channel (1300) comprising an optical fiber, comprising a multipixel detector (2210) comprising a plurality of pixels, and configured to be illuminated by a light beam outputted by the optical fiber, and a processing unit (2220) connected to the multipixel detector (2210) and configured to determine the presence of a blinding attack if a predetermined number of pixels detects light within a predetermined interval. The invention further relates to the use of the receiver (2200) for recognizing blinding attacks in a quantum encrypted channel (1300) and to a method for recognizing blinding attacks in a quantum encrypted channel (1300).
SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION (Republic of Korea)
Inventor
Kwon, Yeongdae
Kim, Taehyun
Cho, Dong Il
Lee, Minjae
Hong, Seokjun
Abstract
Embodiments of the present invention provide a filter for an ion trap device and a designing method therefor, wherein, a conventional RC filter is used, in which an electric field decreases in inverse proportion to the magnitude of capacitance of a capacitor included in the RC filter, and additionally electric fields in opposite directions induced by RF coupling are offset, so that micro vibrations occurring in an ion are suppressed and the degree of integration of an ion trap can be thus increased.
SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION (Republic of Korea)
Inventor
Kwon, Yeongdae
Kim, Taehyun
Cho, Dongil
Park, Yunjae
Lee, Minjae
Abstract
Provided in embodiments of the present invention are an ion trap electrode forming method, and a device using the same, the method being capable of: using an entire electrode region as an object to be optimized since the number of outermost vertices of an electrode, positions thereof, and the like is unrestricted; preventing heating of ions and lifespan deterioration; and optimizing a junction electrode structure that can be utilized for the manufacturing of an ion trap chip for quantum computer and quantum communication implementation.
The present invention relates to an encryption unit (3200) for encrypting at least one packet (P1, P2) according to a predetermined cryptographic protocol, wherein the predetermined cryptographic protocol requires exchanging of service channel information, wherein the service channel information has a first bit length, the encryption unit comprising: a packet analyzer (3210) configured to recognize whether the packet (P1, P2) has unused bits, a packet builder (3220) configured to insert the service channel information in the packet (P1, P2) if the number of unused bits is equal to or larger than the first bit length, and an encryption engine (3230) configured to encrypt the packet (P1, P2) according to the predetermined cryptographic protocol.
G09C 1/00 - Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system
Embodiments of the present invention provide a quantum key distribution stabilization device and method, which can quickly and efficiently compensate for an error occurring because of a temperature change, a polarization change of a transmission path, and the like in an optical system included in a quantum key distribution system, and can reduce costs since a conventional quantum key distribution system can be applied as is.
The present invention relates to a measuring device (3000) for measuring reflection in an optical fiber (1400), the device comprising: emitting means (3100) connected to the optical fiber (1400) and configured to emit light into the optical fiber (1400), measuring means (3300) connected to the optical fiber (1400) and configured to receive a reflected light from the optical fiber (1400), wherein the measuring means comprises a first photon detector (3310) and a second photon detector (3311), wherein the operation of the second photon detector (3311) and/or the reflected light reaching the second photon detector (3311) is controlled based on an output of the first photon detector (3310).
G01M 11/00 - Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
G01D 5/353 - Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using optical means, i.e. using infrared, visible or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
16.
APPARATUS AND METHOD FOR ENHANCING SECRET KEY RATE EXCHANGE OVER QUANTUM CHANNEL IN QUANTUM KEY DISTRIBUTIONSYSTEMS
An apparatus for enhancing secret key rate exchange over quantum channel in QKD systems comprises an emitter system (105) with a quantum emitter (140) and a receiver system (205) with a quantum receiver (240). Emitter system (105) and the receiver system (205) are connected by a quantum channel (600) and a service communication channel (500). User interfaces (120, 220) within the emitter and the receiver systems (105, 205) allow to define a first quantum channel loss budget (tC-D) based on the distance to be covered between the quantum emitter (140) and the quantum receiver (240) and the infrastructure properties of the quantum channel (600) as well as a second quantum channel loss budget (tA-C), wherein the second quantum channel loss budget (tA-C) is associated to the loss within the realm of the emitter system (105). The emitter system (105) 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.
Free-Space key distribution method comprising exchanging information between an emitter (100) and a receiver (200) based on the physical layer wiretap channel model, comprising the steps of randomly preparing (710), at the emitter (100), one qubit encoded with one of two possible non-identical quantum states, sending (720) the encoded qubit to the receiver (200) through a physical layer quantum-enhanced wiretap channel (500), such that an eavesdropper (300) tapping said channel is provided with partial information about the said states only, detecting and measuring (730) the received quantum states, key sifting (740) between the emitter and the receiver through a classical channel, calculating (750, 760) an amount of information available to any eavesdropper (300) based on the detected and received quantum states.
The invention relates to a QKD System Active combiner (200) adapted to be installed in a QKD apparatus, said QKD apparatus comprising an emitter (100), a receiver (110) and QKD systems (102/112), wherein the emitter (100) is adapted to send communication signals to the receiver (110) through the QKD System Active combiner (200), characterized in that the QKD System Active combiner (200) comprises an active attenuation system comprising a processing unit(230) adapted to automatically control at least one variable optical attenuator (150) through a control channel (290) in order to control an attenuation of a signal to be sent to the receiver, and a detector/monitor(240) adapted to monitor the intensity of the signal downstream the attenuation, and wherein the processing unit is adapted to control the variable optical attenuator (150) based on a QBER information or an intensity of a signal received by the receiver, sent by the QKD systems (112) through a classical channel (250).
Some embodiments provide methods and apparatus for quantum random number generation based on a single bit or multi bit Quanta Image Sensor (QIS) providing single-photon counting over a time interval for each of an array of pixels of the QIS, wherein random number data is generated based on the number of photons counted over the time interval for each of the pixels.
A QKD system used to securely exchange encryption keys between an emitter (100) and a receiver (200) modified to accept an additional customization parameter. Said QKD system consists of a QKD transmitter (120) and a QKD receiver (220) capable of implementing a plurality of QKD protocols forming a family of protocols. The QKD transmitter (120) and receiver (220) connected through a quantum channel (500) consist of optical and electronic components adapted to produce and detect a stream of qubits. The qubits (520) exchanged over the quantum channel (500) are grouped into blocks (510) consisting of at least one qubit and whose length is Li (511). For each, block (510) of qubits (520), one of the QKD protocol (530), selected from the family of protocols can be implemented using the emitter (100) and transmitter (200) is used.
The invention relates to a Quantum Key Distribution apparatus (200), for exchanging at least one quantum key with another Quantum Key Distribution apparatus, comprising a Random Number Generator (110) for generating a random bit signal, an electronic driver (140) for transforming a digital signal into an analog signal, an optical platform (150), receiving the signal from the driver, for exchanging, through a quantum channel (170), said quantum key, a clock (120) for synchronizing the working of the QKD apparatus, characterized in that said apparatus comprises an External Random Number Generator input adapted to receive an external random bit generated by an External Random Number Generator (220) connected to said Quantum Key Distribution apparatus, a RNG mixer (210) for receiving outputs from the Random Number Generator and the External Random Number Generator input and generating a random bit signal based on the combination of said outputs, said RNG mixer being disposed downstream the processing unit.
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
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.
An apparatus and method for implementing a secure quantum cryptography system using two non-orthogonal states. For each qubit, the to emitter station prepares a quantum system in one of two non-orthogonal quantum states in the time-basis to code bit values. Intra- and inter-qubit interference is then used to reveal eavesdropping attempts. Witness states are used to help reveal attacks performed across the quantum system separation.
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