Journal of Contemporary Physics (Armenian Academy of Sciences)最新文献_第2页

Features of Heat Propagation in a Multilayer Thermoelectric Sensor when Absorbing Single Photons with Energy of 0.8 eV at Various Depths of a Composite Absorber 多层热电传感器在不同深度吸收能量为0.8 eV的单光子时的热传播特性

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700532

A. A. Kuzanyan, V. R. Nikoghosyan, L. G. Mheryan, A. S. Kuzanyan

{"title":"Features of Heat Propagation in a Multilayer Thermoelectric Sensor when Absorbing Single Photons with Energy of 0.8 eV at Various Depths of a Composite Absorber","authors":"A. A. Kuzanyan, V. R. Nikoghosyan, L. G. Mheryan, A. S. Kuzanyan","doi":"10.1134/S1068337226700532","DOIUrl":"10.1134/S1068337226700532","url":null,"abstract":"Computer simulation was used to study the characteristics of heat propagation processes in a four-layer SiO2 + LaB6/Mo/ La0.99Ce0.01B6/Mo sensor mounted on an Al2O3 substrate. The sensor has a dielectric absorber made of a composite material consisting of SiO2 and 30 vol % LaB6 nanoparticles, a Mo reflector/electrical contact, a La0.99Ce0.01B6 thermoelectric layer, and a Mo heat sink/electrical contact. Heat propagation from the thermalization zone of single photons with an energy of 0.8 eV, localized in the absorber at a depth of 15–80 nm, is examined. Computer modeling was performed using a three-dimensional matrix method based on the equation for heat propagation from a confined volume. The temporal dependences of temperature at various distances from the center of the sensor layer surfaces and the average temperature of the layers surface are studied. The obtained results allow us to calculate the signal-to-noise ratio of the sensor, which determines the efficiency of detecting an absorbed photon. It is shown that this efficiency changes only slightly with changing the depth of the thermalization zone.","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"61 2","pages":"215 - 221"},"PeriodicalIF":0.5,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hard X-Ray Zernike-Type Phase-Contrast Imaging with a Two-Block Crystal System 硬x射线zernike型相衬成像与两块晶体系统

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700507

L. A. Haroutunyan

引用次数: 0

Transimpedance Converter for High-Resistance Sensors Using MOS-Photovaricap mos -光电可变阻高阻传感器的跨阻变换器

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700611

B. O. Semerjyan, D. A. Kananov, M. S. Aleksanyan

引用次数: 0

Spectroscopic Study of Hoechst 33258 Binding to BSA and HSA Hoechst 33258与BSA和HSA结合的光谱研究

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700441

A. P. Antonyan, M. A. Parsadanyan, M. S. Mikaelyan, A. H. Karapetyan, L. M. Yeghsapetyan, P. O. Vardevanyan

引用次数: 0

Nonlinear Beam Dynamics of q-Gaussian Laser Beams in Absorptive Thermal Quantum Plasma: Relativistic and Ponderomotive Nonlinearities 吸收性热量子等离子体中q-高斯激光束的非线性光束动力学：相对论性和有源性非线性

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S106833722670057X

K. Walia, Kriti

{"title":"Nonlinear Beam Dynamics of q-Gaussian Laser Beams in Absorptive Thermal Quantum Plasma: Relativistic and Ponderomotive Nonlinearities","authors":"K. Walia,  Kriti","doi":"10.1134/S106833722670057X","DOIUrl":"10.1134/S106833722670057X","url":null,"abstract":"The current study examines nonlinear beam dynamics of q-Gaussian laser beams propagating through absorptive thermal quantum plasma considering relativistic-ponderomotive nonlinear effects. There is energy dissipation along propagation distance due to linear absorption, thereby causing distance dependent nonlinear response. By making use of quasi-optical approach along with WKB and paraxial approximations, a modified 2nd order propagation equation governing the evolution of beam width is obtained. Numerical simulations are then conducted for exploring influence of key parameters, including absorption coefficient, laser intensity, plasma density, initial beam radius, q-parameter, and Fermi temperature on beam propagation. The outcome clearly shows that relativistic-ponderomotive nonlinear effects greatly enhance nonlinear focusing, whereas absorption counteracts this effect by reducing beam compression and shifting the focal position. A comparative study with both cold quantum and classical relativistic plasma models highlights the essential contribution of quantum effects to laser propagation through dense plasmas.","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"61 2","pages":"165 - 174"},"PeriodicalIF":0.5,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interaction of Monovalent Ions with a Phospholipid Bilayer 一价离子与磷脂双分子层的相互作用

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700489

H. G. Badalyan, M. A. Stepanyan

引用次数: 0

Influence of SC-DSB Signals on the Sensitivity and Selectivity of a UAV Receiver Using LabVIEW 利用LabVIEW研究SC-DSB信号对无人机接收机灵敏度和选择性的影响

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700490

A. Hakhoumian, N. Gasparyan, E. Sivolenko, B. Hovhannisyan

{"title":"Influence of SC-DSB Signals on the Sensitivity and Selectivity of a UAV Receiver Using LabVIEW","authors":"A. Hakhoumian, N. Gasparyan, E. Sivolenko, B. Hovhannisyan","doi":"10.1134/S1068337226700490","DOIUrl":"10.1134/S1068337226700490","url":null,"abstract":"Modern unmanned aerial vehicles (UAVs) critically depend on the stability of radio channels used for control and data transmission. Within the framework of this work, a simulation model of the transmitter–receiver chain of the UAV control radio link was developed in the LabVIEW environment, considering the influence of SC-DSB (Double Sideband Suppressed Carrier) type signals. During the study, SC-DSB signal generation was implemented with adjustable parameters of amplitude, carrier frequency, and modulation bandwidth. The receiver chain was modeled, including an input filter, an amplification stage, a detector, and a signal parameter estimation block. To analyze receiver sensitivity, the minimum input signal level was determined at a specified threshold of demodulation error probability. Selectivity was evaluated by introducing a closely spaced interfering signal in frequency and measuring out-of-band signal suppression. As a result of the simulation, dependencies of the signal-to-noise ratio (SNR), error probability, and interference suppression coefficient on the parameters of the SC-DSB signal were obtained. It is shown that carrier suppression alters the energy distribution in the spectrum and leads to increased requirements for filter bandwidth and the dynamic range of the receiver input stages. The obtained results make it possible to quantitatively assess the impact of SC-DSB signals on the sensitivity and selectivity of a UAV receiver.","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"61 2","pages":"244 - 249"},"PeriodicalIF":0.5,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis and Characterization of Potassium-Sodium Niobate K0.5Na0.5NbO3 Obtained by the Microwave Method 微波法制备铌酸钾钠K0.5Na0.5NbO3的合成及表征

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-09-11 DOI: 10.1134/S1068337226700568

A. A. Sargsyan, T. S. Azatyan, H. A. Aleksanyan, A. A. Petrosyan, S. M. Hayrapetyan, A. A. Khachatryan, V. V. Baghramyan

{"title":"Synthesis and Characterization of Potassium-Sodium Niobate K0.5Na0.5NbO3 Obtained by the Microwave Method","authors":"A. A. Sargsyan, T. S. Azatyan, H. A. Aleksanyan, A. A. Petrosyan, S. M. Hayrapetyan, A. A. Khachatryan, V. V. Baghramyan","doi":"10.1134/S1068337226700568","DOIUrl":"10.1134/S1068337226700568","url":null,"abstract":"A hydrothermal–microwave method was developed for the synthesis of potassium–sodium niobate K0.5Na0.5NbO3 (KNN) followed by high-temperature microwave treatment to obtain KNN ceramics. The synthesis was carried out in a microwave reactor at 210°C for 60 min. A KNN powder was obtained, consisting predominantly of agglomerates formed by nanocrystalline particles (crystallites) with sizes of 20–25 nm. X-ray diffraction analysis confirmed the formation of a single-phase orthorhombic perovskite structure of potassium–sodium niobate at relatively low temperatures (200–220°C). After heat treatment in the temperature range of 660–1100°C, the crystallite size increased up to 90 nm, accompanied by grain growth to the micrometer scale, indicating sintering with the formation of KNN ceramics. Measurements revealed a strong temperature dependence of the dielectric properties of KNN samples. Based on the obtained dielectric parameters, the piezoelectric coefficients were estimated, and according to this theoretical evaluation, the material is capable of exhibiting a significant piezoelectric effect. The maximum piezoelectric coefficient d33 of approximately 160–180 pC/N was observed for samples sintered at 660°C. It was established that precise control of the heat-treatment temperature is crucial for optimizing the structure–property relationship in lead-free KNN-based piezoceramics.","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"61 2","pages":"193 - 200"},"PeriodicalIF":0.5,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Single-Photon Thermoelectric Detector Sensor with Superconducting Molybdenum Absorber 超导钼吸收体单光子热电探测器传感器

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-07-08 DOI: 10.1134/S1068337226700386

A. A. Kuzanyan, V. R. Nikoghosyan, A. S. Kuzanyan

{"title":"Single-Photon Thermoelectric Detector Sensor with Superconducting Molybdenum Absorber","authors":"A. A. Kuzanyan, V. R. Nikoghosyan, A. S. Kuzanyan","doi":"10.1134/S1068337226700386","DOIUrl":"10.1134/S1068337226700386","url":null,"abstract":"The possibility of creating a single-photon detector sensor with a molybdenum absorber and heat sink, lanthanum-cerium hexoboride as the thermoelectric layer, and a sapphire dielectric substrate is considered. Using computer modeling, the absorption of single photons with energies of 0.8, 1.65, and 3.1 eV in a sensor with a surface area of 1 and 0.25 μm2 at an operating temperature of 0.5 and 0.8 K is studied. The results of both heat propagation in a three-layer sensor and determination of the signal power, equivalent noise power, and signal-to-noise ratio are presented. The temporal dependences of the temperature in different areas of the sensor and the average surface temperature of the layers are studied. The maximum temperature, the time to reach the maximum, the time of temperature decay to the background level, and the characteristics of the temperature gradient at the boundaries of the thermoelectric layer are determined. Systematization of the obtained data made it possible to determine the optimal sensor design for efficient registration of single photons from the near infrared to ultraviolet spectral region.","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"61 1","pages":"105 - 111"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Hydrogen Molecule in the Heitler–London Model in First-Order Perturbation Theory 一阶微扰理论中Heitler-London模型中的氢分子

IF 0.5 4区物理与天体物理

Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2026-07-08 DOI: 10.1134/S1068337226700362

V. A. Harutyunyan

引用次数: 0