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О ПРОСТОМ ЭВРИСТИЧЕСКОМ ВЫВОДЕ ФОРМУЛЫ ШЕННОНА ДЛЯ КАНАЛА СВЯЗИ С НЕПРЕРЫВНЫМИ ПЕРЕМЕННЫМИ В КВАНТОВОМ СЛУЧАЕ
Журнал экспериментальной и теоретической физики. 2021. Т. 159. № 3. С. 434–457.
Арбеков И. М., Молотков С. Н., Синильщиков И. В.
The aim of the paper is the derivation of formulas for the capacities of a classical–quantum communication channel with Gaussian noise, which are analogs of the classical capacities and arise in many problems of quantum information theory, on a simple, heuristic and physically intuitively clear level. The classical capacity of a classical communication channel with limited frequency band and Gaussian information states diverges as noise tends to zero. In a consistent quantum consideration, the divergence is removed, which is a consequence of the fundamental physical principle of indistinguishability of particles—bosons in information states.
Hazarika A. P., Das A., Das S. K. et al., Physica B: Condensed Matter 2026 Vol. 738 Article 418803
Lemon grass (Cymbopogon citratus, LG-SiO2), horsetail (Equisetum debile, SG-SiO2), and cassava leaves (Manihot esculenta, CL-SiO2) were used to green-synthesize silica (SiO2) nanoparticles (NPs). While LG-SiO2 and SG-SiO2 had strong (101) peaks and a large 22° amorphous peak, XRD of CL-SiO2 verified crystallinity. LG-SiO2 (agglomerated porous), SG-SiO2 (rectangular-cube agglomerates), and CL-SiO2 (flake agglomerates) had different morphologies. The TEM image of LG-SiO2 revealed agglomerated ...
Added: June 4, 2026
Kornbleuth M., Opher M., Drake J. F. et al., Astrophysical Journal 2026 Vol. 1004 No. 1 Article 1
The shape of the heliosphere, regarded as comet-like since the 1960s, has recently been the subject of intense debate in the last decade. There is disagreement as to whether the heliospheric tail extends to ∼10,000 au in a comet-like shape or if it is short (∼400 au) with a split. Energetic neutral atom (ENA) maps from ...
Added: June 3, 2026
Карцев А. И., Nishant T., Saswata G. et al., Journal of Materials Chemistry C 2026 Article -
Overheating remains a critical limitation in high-performance electronic and computing systems,
necessitating the development of efficient thermal management fluids. In this work, a magnetically
responsive hybrid ferrofluid was developed by incorporating two-dimensional hexagonal boron nitride
(2D-hBN) nanosheets into a Mn–Zn–ferrite-based ferrofluid. The hybrid system retains magnetic
responsiveness while leveraging the high in-plane thermal conductivity and chemical stability of 2D-hBN
nanosheets. ...
Added: June 2, 2026
Fortuna A. S., A.I. Kartsev, Gorshenkov M. V. et al., Journal of Alloys and Compounds 2026 Vol. 1070 Article 188711
The τ-phase in Mn-Al-Ga alloys is a promising candidate for rare-earth-free permanent magnets. This study re-veals that the τ(γ₂)-phase in rapidly quenched Mn55Al36Ga9 ribbons contains a high density of dislocations, which
form antiphase boundaries (APBs). Using transmission electron microscopy and density functional theory, we
demonstrate that Mn atoms at these APBs couple antiferromagnetically. This antiferromagnetic interaction is
identified ...
Added: June 2, 2026
Dikhtievskaya K., Argunov E., Карцев А. И. et al., The Journal of Physical Chemistry Letters 2026 Vol. 17 No. 17 P. 4999–5004
In this study we revealed the effect of scandium doping on the electronic and superconducting properties of the MgB2 compound. Calculations demonstrate that Sc substitutes for Mg atoms, acting as an electron donor. Mg substitution diminishes the density of states in the σ-band and attenuates the electron–phonon coupling, thereby elucidating the reduction in critical temperature. Simultaneously, ...
Added: June 2, 2026
Duran E. ., Pulgar A., Izquierdo R. et al., Physica Status Solidi (A) Applications and Materials 2026 Vol. 223 No. 7 Article e202500942
Ceramic superconductors exhibit remarkable properties, including zero electrical resistance and potent magnetic behavior, operating at temperatures as high as the boiling points of liquid nitrogen (77 K) and liquid hydrogen (20 K). These characteristics position them as key enablers for sustainable technologies spanning electric propulsion, lossless energy transmission, advanced medical imaging, and quantum computation. This review presents ...
Added: June 1, 2026
Borisov V., Danilov V., Электросвязь 2025 № 12 С. 73–84
Представлены результаты математического моделирования процесса полевой эмиссии из катода малых размеров – одного из основных физических процессов, обеспечивающих работы многих электронных устройств, в частности FED-дисплеев (устройства, работающие на принципе полевой эмиссии), кантилеверов и т.д. Дается краткий обзор текущих результатов в области исследования, обосновывается актуальность задачи, приводятся примеры наиболее вероятного использования результатов решения задачи. Обсуждаются физические ...
Added: May 29, 2026
Jiang Q., Fang J., Chen J. et al., Science China Information Sciences 2026 Vol. 69 No. 6 Article 162402
Resonators based on nanoelectromechanical systems (NEMS) using two-dimensional (2D) materials with high-quality factors and excellent electrical control are critical for tunable coherent phonon dynamics, resonant sensors and wireless communications. However, their performance is fundamentally limited by the lack of a unified framework governing energy dissipation mechanisms and their electrical tunability. Here, we synergistically modulate both ...
Added: May 28, 2026
Elesin L., Shilov A., Jana S. et al., Advanced Functional Materials 2026 P. 1–10
Thermoelectric materials, long explored for energy harvesting and thermal sensing, convert heat directly into electrical signals. Extending their application to the terahertz (THz) frequency range opens opportunities for low-noise, bias-free THz detection, yet conventional thermoelectrics lack the sensitivity required for practical devices. Thermoelectric coefficients can be strongly enhanced near van Hove singularities (VHS), though these ...
Added: May 28, 2026
Degtyarev A., Bakhurin S., Yudin N., DSPA 2026 P. 1–6
This paper investigates one possible solution to the problem of self-interference cancellation (SIC) arising in the design of in-band full-duplex (IBFD) communication systems. Self-interference cancellation is performed in the digital domain using multilayer nonlinear models adapted via gradient-based optimization. The presence of local minima and saddle points during the adaptation of multilayer models limits the ...
Added: May 26, 2026
Qian X., Deng Y., Lev N. Shchur et al., Physica A: Statistical Mechanics and its Applications 2026 Vol. 696 Article 131679
We perform a Monte Carlo analysis of the Ising model on many three-dimensional lattices. By means of finite-size scaling we obtain the critical points and determine the scaling dimensions. As expected, the critical exponents agree with the three-dimensional Ising universality class for all models. The irrelevant field, as revealed by the correction-to-scaling amplitudes, appears to ...
Added: May 24, 2026
Melentiev P. N., Калмыков А. С., Гритченко А. С. et al., Успехи физических наук 2024 Т. 194 № 11 С. 1130–1145
Представлен краткий обзор достигнутого уровня оптических методов детектирования единичных молекул в биомедицинских приложениях. Показано, что регистрация флуоресценции единичных молекул красителей, ковалентно связанных с антителами (биомолекулами), совместно с использованием современных методов нанофотоники может быть применена для решения различных задач в биологии и медицине: визуализации биомолекул, токсинов, вирусных частиц, определения ультранизких концентраций аналитов напрямую во взятой пробе, ...
Added: May 21, 2026
Antsiferov P.S., Stepanov L.V., Matiukhin N. D., Review of Scientific Instruments 2025 Vol. 96 No. 12 Article 123506
The article presents the discharge plasma based source of extreme ultraviolet (EUV) radiation. The discharge circuit has been driven by means of stripe line storage with working voltage 10.5 kV. The main feature of the proposed source is that plasma electrons acquire the energy, necessary for the production of multiply charged ions with ionization potentials ...
Added: May 20, 2026
Анциферов П. С., Степанов Л. В., Матюхин Н. Д., Оптика и спектроскопия 2026 Т. 134 № 2 С. 214–218
Сообщено о разработке системы регистрации спектров на ПЗС-линейке для уникального ВУФ спектрометра, построенного на основе сферической дифракционной решетки с радиусом 6.65 m. Была использована линейка HAMAMATSU S11156-2048-02, которая устанавливалась по касательной к окружности Роуланда с возможностью механического перемещения для сканирования спектра. Были получены спектрограммы в диапазоне длин волн 2130-2270 Angstrem. Описана методика сшивки регистрируемых спектральных ...
Added: May 20, 2026
Shipilov F., Barnyakov A., Ivanov A. et al., / Series Physics "arxiv.org". 2026.
A fast simulation of the detector response is a vital task in high-energy physics (HEP). Traditional Monte-Carlo methods form the backbone of modern particle physics simulation software but are computationally expensive. We present a machine-learning-based approach to fast simulation of the Focusing Aerogel Ring Imaging Cherenkov (FARICH) detector response. Given a particle track and momentum, ...
Added: May 19, 2026
Ponosova A., Zhluktova I., Ruzhitskaya D. et al., Applied Physics Letters 2025 Vol. 127 No. 19 P. 194002
Quantum key distribution systems offer cryptographic security, provided that all their components are thoroughly characterized. However, certain components might be vulnerable to laser-damage attacks, particularly when subjected to untested laser parameters. Here, we show that exposing 1550-nm fiber-optic isolators to 1061-nm sub-nanosecond pulsed illumination with 1.16 W average power permanently degrades their isolation performance at ...
Added: December 5, 2025
Daniil Trefilov, Sixto X., Zapatero V. et al., Optica Quantum 2025 Vol. 3 No. 5 P. 417–431
The decoy-state method is a prominent approach to enhance the performance of quantum key distribution (QKD) systems that operate with weak coherent laser sources. Due to the limited transmissivity of single photons in optical fiber, current experimental decoy-state QKD setups increase their secret key rate by raising the repetition rate of the transmitter. However, this ...
Added: September 20, 2025
V. I. Morozov, O. O. Evsyutin, S. I. Nefedov, Problems of Information Transmission 2025 Vol. 61 No. 1 P. 8–26
One of the main applications of quantum communication is quantum key distribution, which solves the problem of secure distribution of cryptographic keys between remote users. This paper investigates the performance of a phase-time coding quantum key distribution protocol belonging to the BB84 protocol family. We construct a simulation model that takes into account the peculiarities ...
Added: April 22, 2025
Makarov V., Abrikosov A., Chaiwongkhot P. et al., Physical Review Applied 2024 Vol. 22 No. 4 P. 044076-1–044076-34
A commercial quantum key distribution (QKD) system needs to be formally certified to enable its wide deployment. The certification should include the system’s robustness against known implementation loopholes and attacks that exploit them. Here we ready a fiber-optic QKD system for this procedure. The system has a prepare-and-measure scheme with decoy-state BB84 protocol, polarization encoding, ...
Added: December 8, 2024
Ruzhitskaya D., Zhluktova I., Ponosova A. et al., Conference on Lasers and Electro-Optics/Europe (CLEO/Europe 2023) and European Quantum Electronics Conference 2023 Article eb_p_14
Quantum key distribution (QKD) systems provide quantum-safe key exchange. Therefore, complete security analysis of implementations of QKD protocols is in the focus of interest of a worldwide information-security community. For today, a number of QKD loopholes are closed by countermeasures, which are also considered in emerging QKD security evaluation and certification [1–3]. However, new threats ...
Added: September 13, 2024
Tretiakov V. V., K. S. Kravtsov, Klimov A. N. et al., Laser Physics Letters 2024 Vol. 21 No. 6 Article 065206
We demonstrate a compensation-free approach to the realization of multi-mode delay interferometers, mainly for use in phase-encoded quantum key distribution (QKD). High interference visibility of spatially multi-mode beams in unbalanced Michelson or Mach–Zehnder interferometers with a relatively wide range of delays is achieved by the appropriate choice of the transverse size of the beam. We ...
Added: May 11, 2024
Khmelev A., Duplinsky A, Bakhshaliev R et al., Optics Express 2024 Vol. 32 No. 7 P. 11964–11978
The Micius satellite is the pioneering initiative to demonstrate quantum teleportation, entanglement distribution, quantum key distribution (QKD), and quantum-secured communications experiments at the global scale. In this work, we report on the results of the 600-mm-aperture ground station design which has enabled the establishment of a quantum-secured link between the Zvenigorod and Nanshan ground stations ...
Added: April 25, 2024
Miller A., Pismenuk L., Duplinsky AV et al., EPJ QUANTUM TECHNOLOGY 2023 Vol. 10 No. 1 Article 52
A satellite-constellation based global quantum network could allow secure quantum communication between remote users worldwide. Such a constellation could be formed of micro- or even nanosatellites, which have the advantage of being more cost-effective than larger expensive spacecrafts. At the same time, the features of quantum communication impose a number of technical requirements that are ...
Added: April 25, 2024
Automated verification of countermeasure against detector-control attack in quantum key distribution
Acheva P., Zaitsev K., Zavodilenko V. V. et al., EPJ QUANTUM TECHNOLOGY 2023 Vol. 10 No. 1 Article 22
Attacks that control single-photon detectors in quantum key distribution using tailored bright illumination are capable of eavesdropping the secret key. Here we report an automated testbench that checks the detector’s vulnerabilities against these attacks. We illustrate its performance by testing a free-running detector that includes a rudimentary countermeasure measuring an average photocurrent. While our testbench ...
Added: April 19, 2024