arXiv subjects

Y. V. Kurochkin

Publications and source records attributed to Y. V. Kurochkin.

14 recordsLinked to original sources

arXiv2022

Dead time duration and active reset influence on the afterpulse probability of InGaAs/InP single-photon avalanche diodes

We have performed a detailed study of the dependence of afterpulse probability in InGaAs/InP sine-gated SPAD on the dead time and the existing approach for its implementation. We demonstrated an electrical scheme combining sinusoidal gating and active reset. We have shown when such solutions are beneficial from the key distribution point of view and enough to use a simple scheme with a snatching comparator. We have also proposed a precise method for measuring the afterpulse and presented a model describing the non-markovian dynamic of this effect. We have demonstrated that our afterpulsing measurement approach makes these measurements less dependent on the parameters of the flow of the diode and the laser pulses power changes, in contrast to the other methods considered in this paper.

quant-ph↗

arXiv2021

Quantum cryptography in the aspect of popularization of science and development of professional and technical qualifications

The aura of mystery surrounding quantum physics makes it difficult to advance quantum technologies. Demystification requires methodological techniques that explain the basics of quantum technologies without metaphors and abstract mathematics. The article provides an example of such an explanation for the BB84 quantum key distribution protocol based on phase coding. This allows you to seamlessly get acquainted with the real cryptographic installation QRate, used at the WorldSkills competition in the competence of "Quantum Technologies".

physics.pop-ph↗

arXiv2021

Investigation of the dependence of noise characteristics of SPAD on the gate parameters in sine-wave gated single-photon detectors

In this paper, we have investigated a self-developed sine wave gated (SWG) single-photon detector (SPD) for 1550 nm wavelength primary for quantum key distribution (QKD) usage. We have investigated different gate parameters` influence on the SPD`s noise characteristics. We have admitted that with an increase of gating voltage and constant value of quantum efficiency (QE), the dark count rate (DCR) decreases. There have been made some recommendations to improve SPD`s and whole QKD device's characteristics based on these observations. There have been discovered the quick rise of the DCR value with the increase of gating voltage above some certain value and this value was different for different detectors. It has been shown that universal empirical dependence compilation to connect control and operational parameters of SPD is a non-trivial task.

quant-ph↗

arXiv2020

Quantum soft filtering for the improved security analysis of the coherent one-way quantum-key-distribution protocol

A precise security analysis of practical quantum key distribution (QKD) systems is an important step for improving their performance. Here we consider a class of quantum soft filtering operations, which generalizes the unambiguous state discrimination (USD) technique. These operations can be applied as a basis for a security analysis of the original coherent one-way (COW) QKD protocol since their application interpolates between beam-splitting (BS) and USD attacks. We demonstrate that a zero-error attack based on quantum soft filtering operations gives a larger amount of the information for Eve at a given level of losses. We calculate the Eve information as a function of the channel length. The efficiency of the proposed attack highly depends on the level of the monitoring under the maintenance of the statistics of control (decoy) states, and best-case results are achieved in the case of the absence of maintenance of control state statistics. Our results form additional requirements for the analysis of practical QKD systems based on the COW QKD protocol and its variants by providing an upper bound on the security.

quant-ph↗

arXiv2019

Modular quantum key distribution setup for research and development applications

Quantum key distribution (QKD), ensuring the unconditional security of information, attracts a significant deal of interest. An important task is to design QKD systems as a platform for education as well as for research and development applications and fast prototyping new QKD protocols. Here we present a modular QKD setup driven by National Instruments (NI) cards with open source LabView code, open source Python code for post-processing procedures, and open source protocol for external applications. An important feature of the developed apparatus is its flexibility offering possibilities to modify optical schemes and verify novel QKD protocols. Another distinctive feature of the developed setup is the implementation of the decoy-state protocol, which is a standard tool for secure long-distance quantum communications. By testing the plug-and-play scheme realizing BB84 and decoy-state BB84 QKD protocols, we demonstrate that developed QKD setup shows a high degree of robustness beyond laboratory conditions. We demonstrate the results of the use of the developed modular setup for urban QKD experiments.

quant-ph↗

arXiv2019

Symmetric blind information reconciliation for quantum key distribution

Quantum key distribution (QKD) is a quantum-proof key-exchange scheme which is fast approaching the communication industry. An essential component in QKD is the information reconciliation step, which is used for correcting the quantum-channel noise errors. The recently suggested blind reconciliation technique, based on low-density parity-check (LDPC) codes, offers remarkable prospectives for efficient information reconciliation without an a priori error rate estimation. We suggest an improvement of the blind-information-reconciliation protocol promoting a significant increase in the efficiency of the procedure and reducing its interactivity. The proposed technique is based on introducing symmetry in operations of parties, and the consideration of results of unsuccessful belief-propagation decodings.

quant-ph↗

arXiv2018

Educational potential of quantum cryptography and its experimental modular realization

The fundamental principles of quantum mechanics are considered to be hard for understanding by unprepared listeners, many attempts of its popularization turned out to be either difficult to grasp or incorrect. We propose quantum cryptography as a very effective tool for quantum physics introduction as it has the desired property set to intrigue students and outline the basic quantum principles. A modular desktop quantum cryptography setup that can be used for both educational and research purposes is presented. The carried out laboratory and field tests demonstrated usability and reliability of the developed system.

physics.ed-ph↗

arXiv2018

Quantum-secured data transmission in urban fibre-optic communication lines

Quantum key distribution (QKD) provides theoretic information security in communications based on the laws of quantum physics. In this work, we report an implementation of quantum-secured data transmission in the infrastructure of Sberbank of Russia in standard communication lines in Moscow. The experiment is realized on the basis of already deployed urban fiber-optics communication channels with significant losses. We realize the decoy-state BB84 QKD protocol using the one-way scheme with polarization encoding for generating keys. Quantum-generated keys are then used for continuous key renewal in the hardware devices for establishing a quantum-secured VPN Tunnel between two offices of Sberbank. The hybrid approach used offers possibilities for long-term protection of the transmitted data; it is promising for integrating into the already existing information security infrastructure.

quant-ph↗

arXiv2018

Quantum-secured blockchain

Blockchain is a distributed database which is cryptographically protected against malicious modifications. While promising for a wide range of applications, current blockchain platforms rely on digital signatures, which are vulnerable to attacks by means of quantum computers. The same, albeit to a lesser extent, applies to cryptographic hash functions that are used in preparing new blocks, so parties with access to quantum computation would have unfair advantage in procuring mining rewards. Here we propose a possible solution to the quantum era blockchain challenge and report an experimental realization of a quantum-safe blockchain platform that utilizes quantum key distribution across an urban fiber network for information-theoretically secure authentication. These results address important questions about realizability and scalability of quantum-safe blockchains for commercial and governmental applications.

quant-ph↗

arXiv2018

Practical cryptographic strategies in the post-quantum era

We review new frontiers in information security technologies in communications and distributed storage technologies with the use of classical, quantum, hybrid classical-quantum, and post-quantum cryptography. We analyze the current state-of-the-art, critical characteristics, development trends, and limitations of these techniques for application in enterprise information protection systems. An approach concerning the selection of practical encryption technologies for enterprises with branched communication networks is introduced.

quant-ph↗

arXiv2017

Demonstration of a quantum key distribution network in urban fibre-optic communication lines

We report the results of the implementation of a quantum key distribution (QKD) network using standard fibre communication lines in Moscow. The developed QKD network is based on the paradigm of trusted repeaters and allows a common secret key to be generated between users via an intermediate trusted node. The main feature of the network is the integration of the setups using two types of encoding, i.e. polarisation encoding and phase encoding. One of the possible applications of the developed QKD network is the continuous key renewal in existing symmetric encryption devices with a key refresh time of up to 14 s.

quant-ph↗

arXiv2017

Analysis of coherent quantum cryptography protocol vulnerability to an active beam-splitting attack

We consider a new type of attack on a coherent quantum key distribution protocol [coherent one-way (COW) protocol]. The main idea of the attack consists in measuring individually the intercepted states and sending the rest of them unchanged. We have calculated the optimum values of the attack parameters for an arbitrary length of a channel length and compared this novel attack with a standard beam-splitting attack.

quant-ph↗

arXiv2017

Quantum key distribution protocol with pseudorandom bases

Quantum key distribution (QKD) offers a way for establishing information-theoretically secure communications. An important part of QKD technology is a high-quality random number generator (RNG) for quantum states preparation and for post-processing procedures. In the present work, we consider a novel class of prepare-and-measure QKD protocols, utilizing additional pseudorandomness in the preparation of quantum states. We study one of such protocols and analyze its security against the intercept-resend attack. We demonstrate that, for single-photon sources, the considered protocol gives better secret key rates than the BB84 and the asymmetric BB84 protocol. However, the protocol strongly requires single-photon sources.

quant-ph↗

arXiv2016

Post-processing procedure for industrial quantum key distribution systems

We present algorithmic solutions aimed on post-processing for industrial quantum key distribution systems with hardware sifting. The main steps of the procedure are error correction, parameter estimation, and privacy amplification. Authentication of a classical public communication channel is also considered.

quant-ph↗