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Graphene two terminal detector as THz mixer
Journal of Physics: Conference Series. 2021. Vol. 2086. No. 1. Article 012054.
The growing requirements for mobile communication networks (data transfer rates over 100 Gbps) makes it necessary to use carrier signal with a frequency of at least 100 GHz. This requires the development of cheap and broadband sub-terahertz (sub-THz) detectors. Here we report on our recent efforts toward the development of a heterodyne sub-THz detector based on a single layer graphene two-terminal device integrated with a bowtie antenna on a sapphire substrate. Our detector operates at frequency of 140 GHz, which corresponds to the maximum transmission of THz radiation in the Earth's atmosphere. The heterodyne detection is achieved by quasi-optical coupling of signals from two sub-THz radiation sources to the same detector. The measured frequency bandwidth is 5.8 GHz.
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
Malinovsky A. M., Пилипенко С. В., Mikhalchenko A. O. et al., Astronomy Reports 2026 Vol. 70 P. 1–6
Radiation from rotational transitions of CO molecules in distant galaxies creates a chaotic background with an intensity reaching 1000 Jy/sr at a wavelength of approximately 1 mm. This background will pose a serious problem, when measuring spectral distortions of the cosmic microwave background, in particular, the mu-distortion, which presumably has an intensity of less than ...
Added: May 19, 2026
Kaveev A. K., Fedorov V. V., Pavlov A. V. et al., Journal of Materials Chemistry C 2026 Vol. 14 No. 7 P. 2697–2705
Bismuth nanostructures represent a promising material platform for semiconductor nanooptoelectronics and colorimetry owing to the multi-colored light reflection and quantum confinement. In this work, we study the photoluminescent properties of bismuth nanostructures grown using molecular beam epitaxy on the planar CaF2/Si(111) surface. We demonstrate the different surface morphologies of Bi, ranging from planar films obtained ...
Added: May 19, 2026
Pavlova T., V.M. Shevlyuga (Шевлюга В. М., Applied Surface Science 2026 Vol. 736 P. 166813–166813
The objective of miniaturizing doped areas in silicon, with the ultimate goal of achieving atomic-precision doping, requires a fundamental understanding of the dopant incorporation process at the atomic level. We present a combined scanning tunneling microscopy (STM) and density functional theory (DFT) investigation of single phosphorus atom incorporation into the Si(100) surface. Phosphorus was supplied ...
Added: May 19, 2026
Pasternak D., Romshin A., Khmelnitsky Р. et al., Carbon 2026 Vol. 256 Article 121655
A single-photon source (SPS) is a key component required for quantum communication devices. We report the
discovery of bright diamond-based SPS created by nature. It is shown that narrow (≤2 nm) lines observed in the
500-800 nm range in photoluminescence (PL) spectra of the surface layer of untreated Yakut diamonds rich in
nitrogen and hydrogen are linked to ...
Added: May 19, 2026
A.M. Smirnov, Kurtina D. A., Saitov S. R. et al., Optical Materials: X 2026 Vol. 30 Article 100441
Chiral semiconductor nanostructures and nanoparticles are promising materials for applications in biological sensing, enantioselective separation, photonics, and spin-polarized devices. Here we performed a detailed analysis of optical properties of chiral CdSe nanoplatelets with thickness of 2 and 3 monolayers (ML) with Nacetyl-L-cysteine ligands. We studied the absorption spectra peculiarities, analyzed time-resolved photoluminescence and investigated circular ...
Added: May 18, 2026
Smirnov A., Mantsevich V. N., Saitov S. R. et al., Journal of Applied Physics 2026 Vol. 139 Article 185702
This work presents a comprehensive investigation into the temperature-dependent thermally stimulated conductivity and photoconductivity of vacuum-annealed thin films based on core–shell CdSe/CdS nanoplatelets passivated with oleic acid ligands. Controlled thermal annealing under vacuum conditions leads to a substantial increase in both dark and photoinduced conductivity, which is primarily attributed to partial desorption of the ligands. ...
Added: May 18, 2026
Масютин Д. А., Moiseev E., Komarov S. et al., Письма в Журнал технической физики 2026 Т. 52 № 7 С. 27–30
Исследованы инжекционные полупроводниковые микролазеры с кольцевым резонатором радиусом 15 мкм с несимметричным расположением внутреннего отверстия резонатора. Показано, что асимметрия обеспечивает формирование в диаграмме направленности двух лепестков излучения, разориентированных на 50° относительно оси смещения внутреннего отверстия. Измеренная добротность резонаторов сопоставима с добротностью дисковых резонаторов и находится на уровне ∼ 10^6. ...
Added: May 18, 2026
Rathish S., Andrey S. Vasenko, Thazhathenair A. et al., The Journal of Physical Chemistry Letters 2026 Vol. 17 No. 18 P. 5386–5394
We demonstrate and rationalize the effect of Au nanoparticles (NPs) on the hierarchical g-C3N4/CeO2 heterojunction. g-C3N4/CeO2 decorated with monodispersed plasmonic Au NPs was synthesized. Detailed analyses showed that CeO2 nanocubes and monodispersed Au NPs were evenly distributed over the 2D g-C3N4 surface, forming a robust interface enriched with abundant active sites. The structure enabled efficient separation of photogenerated charge ...
Added: May 16, 2026
Das A., Paul R., Sharma N. et al., Colloids and Surfaces A: Physicochemical and Engineering Aspects 2026 Vol. 728 P. 138830
Niobium-doped TiO2 (Nb-TiO2), demonstrates dual functionality as an efficient photocatalyst for dye degradation and a promising photoelectrocatalyst for water oxidation. Nb incorporation via a facile hydrothermal method was confirmed by XRD (Rietveld refinement), XPS, TEM, FT-IR, Raman, and BET analyses, indicating successful lattice doping and structural modification. Photocatalytic dye degradation experiments were conducted using a model ...
Added: May 16, 2026
I. V. Kolokolov, V. V. Lebedev, Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2026 Vol. 113 No. 5 Article 054117
We theoretically investigate the correlation functions of the phase of a light wave propagating through a
turbulent medium. We use an equation for the logarithm of a wave packet envelope, which includes a secondorder
nonlinear term. Based on this equation, we develop a diagrammatic technique to calculate corrections
to the correlation function obtained in the linear approximation. We ...
Added: May 15, 2026
Ивашенцева И. В., Федотов П. В., Каурова Н. С. et al., Журнал технической физики 2024 Т. 94 № 8 С. 1391–1397
A technology for sensitizing a structure consisting of a graphene nanoribbon (GNR) on a Si/GNR silicon substrate in the near-IR range of the electromagnetic spectrum is presented. This technology is based on doping the GNR with He4. A more than 25-fold increase in the response at a wavelength of 1.35 μm in the Si/GNR/He4 structure, ...
Added: December 23, 2025
Mehrabi-Kalajahi S., Ostovari Moghaddam A., Akbarpour S. et al., ACS Applied Energy Materials 2025 Vol. 8 No. 12 P. 8524–8531
High-entropy materials provide an interesting route for developing highly active electrocatalysts owing to their tunability and numerous active sites; however, their performance can be further improved with interfacial engineering in nanocomposite catalysts. In this study, (CoFeMnCuNiCr)3O4 high-entropy oxide (HEO) nanoparticles were synthesized and grafted onto graphene (HEO–G), graphene oxide (HEO–GO), and reduced graphene oxide (HEO–rGO) supports. ...
Added: June 16, 2025
A. N. Lyubchak, K. V. Shein, G.N. Goltsman et al., St. Petersburg Polytechnical University Journal: Physics and Mathematics 2024 Vol. 17 No. 3.2 P. 116–120
Terahertz (THz) integrated circuits is a promising platform to create low cost and efficient components for high-speed sixth-generation (6G) communication networks. One of the key components for this application is detectors and mixers integrated on THz silicon waveguide. Graphene, due to its unique and tunable properties such as zero band gap, high charge mobility and low electronic heat capacity, has ...
Added: November 5, 2024
Bondareva P., Shein K., Lyubchak A. N. et al., St. Petersburg Polytechnical University Journal: Physics and Mathematics 2024 Vol. 17 No. 3.2 P. 46–51
Graphene, due to its record low electron heat capacity and weak electron-phonon coupling at low temperatures, is considered as a promising material for creating terahertz hot electron bolometers. The main challenge to the development of such devices is the weak dependence of graphene resistance on temperature. Here we demonstrate measurement system based on Johnson noise ...
Added: November 5, 2024
Kravtsov M., Shilov A. L., Yang Y. et al., Nature Nanotechnology 2025 Vol. 20 No. 1 P. 51–56
Light incident upon materials can induce changes in their electrical conductivity, a phenomenon referred to as photoresistance. In semiconductors, the photoresistance is negative, as light-induced promotion of electrons across the bandgap enhances the number of charge carriers participating in transport. In superconductors and normal metals, the photoresistance is positive because of the destruction of the ...
Added: October 9, 2024
Evlashin S., Fedorov F. S., Chernodoubov D. A. et al., Journal of Electroanalytical Chemistry 2024 Vol. 956 Article 118091
Carbon materials are of outstanding interest for use in energy sources. One of the latest achievements in improving their specific characteristics is the doping of carbon materials with various heteroatoms. However, the mechanisms that lead to improved performance remain unexplored. In this study, we investigated the influence of structural defects and incorporated heteroatoms on the ...
Added: February 9, 2024
P. I. Bondareva, K. V. Shein, A. N. Lyubchak et al., St. Petersburg Polytechnical University Journal: Physics and Mathematics 2023 Vol. 16 No. 3.1 P. 128–132
In this paper we investigate a novel approach to inventing graphene-based sub-ter- ahertz bolometers using noise thermometry. Graphene is a unique material for detecting radi- ation in the sub-terahertz (0.1–1 THz) and terahertz (1–10 THz) ranges due to its record low electron heat capacity and weak electron-phonon coupling. This results in sufficient heating of graphene ...
Added: February 5, 2024
Арбузов А. А., Можжухин С. А., Лотоцкий М. В. et al., Журнал прикладной химии 2023 Т. 96 № 2 С. 217–224
В работе приведены результаты исследования взаимодействия композитов MgH2 с графеноподобным
или никель-графеновым материалом, полученных механохимической обработкой в атмосфере водорода, с водой и растворами лимонной кислоты различной концентрации. Установлено, что взаимодействие водного раствора лимонной кислоты с композитами характеризуется высокой скоростью:
98%-ный выход водорода достигается при мольном соотношении MgH2:лимонная кислота = 1:1.
Разработано устройство для получения компримированного водорода из композитов, ...
Added: September 29, 2023
Minkin A., Lebedeva I., Popov A. et al., Physical Review B: Condensed Matter and Materials Physics 2023 Vol. 108 No. 8 Article 085411
The potential energy surface (PES) of the interlayer interaction of infinite twisted bilayer graphene is calculated for a set of commensurate moiré patterns using the registry-dependent Kolmogorov-Crespi empirical potential. The calculated PESs have the same shape for all considered moiré patterns, and the unit cell size of the PESs is inversely related to the unit ...
Added: August 22, 2023
Смирнов И. А., Черкесова Л. В., Жебрун Е. А. et al., Изд-во Томского политехнического университета, 2019.
The high mobility of charge carriers in graphene makes it promising and prospective material for using for various applications as a future base for nanoelectronics and possible replacement of silicon in integrated circuits, and contributes to the creation of radioelectronic devices and arrangements microwave, Sub-THz and THz-bands. Pro-gress in the production and formation of curly ...
Added: May 11, 2023