2020, Lebedinskii, Y. Y., Borisyuk, P. V., Chubunova, E. V., Kolachevsky, N. N., Vasiliev, O. S., Tkalya, E. V., Лебединский, Юрий Юрьевич, Борисюк, Петр Викторович, Чубунова, Елена Витальевна, Васильев, Олег Станиславович, Ткаля, Евгений Викторович

© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimCurrently, an urgent task related to creating a nuclear frequency standard is the identification of a low-lying nuclear state in the thorium-229 isotope. Herein, a method for measuring the single-photon energy during the decay of an isomeric thorium-229 nucleus implanted in a wide-gap dielectric SiO2 (Eg = 9 eV) is developed. The proposed method utilizes thin silicon oxide layers obtained by thermal oxidization of the pure silica wafers, which allows measurement of the energy of photons in the ultraviolet (UV) range using an electronic spectrometer. The modeling study of electronic state excitation is provided via UV radiation from Kr, Xe, and D resonance discharging lamps. The obtained spectra are analyzed, and a method for determining the UV photon's energy is proposed.

2020, Vasilyev, O. S., Borisyuk, P. V., Lebedinskii, Y. Y., Васильев, Олег Станиславович, Борисюк, Петр Викторович, Лебединский, Юрий Юрьевич

© 2020, Pleiades Publishing, Ltd.Abstract: The results of the formation of an original material based on thin films of metal nanoclusters and the investigation of its chemical composition, surface morphology, and structure are presented. Monodisperse thin films comprised of individual nanoclusters of Ta, Mo, and Ni metals were manufactured by gas-phase magnetron sputtering. Images of the surface were obtained by scanning electron microscopy and it was shown that the Ta and Mo films had a well-developed porous structure and consisted of separate nanoclusters contacting each other only at the interface. The chemical composition of the resulting films immediately after deposition (in situ) and after exposure to the atmosphere (ex situ) was investigated by X-ray photoelectron spectroscopy. It was shown that the exposure to the atmosphere led to the oxidation of the obtained films, namely, to the formation of oxide shells in nanoclusters that formed the films. The possibility of creating thin-film photodetectors based on nanocluster films to detect the decay of isomeric nuclear transition in 229Th nuclei is discussed.

2017, Васильев, О. С., Борисюк, П. В., Козлова, Т. И., Лебединский, Ю. Ю., Борисюк, Петр Викторович, Лебединский, Юрий Юрьевич, Козлова, Татьяна Ивановна, Васильев, Олег Станиславович

The results of the study of electron properties evolution of monodisperse thin films consisted of Ta and Mo metal nanoclusters deposited onto the SiO2/Si(001) surface with magnetron sputtering method are presented. The changes in chemical composition and electron structure of the samples were controlled by means of X-ray photoelectron spectroscopy in the UHV analysis chamber of the Multiprobe MXPS RM VT AFM-25 surface analysis system. Susceptibility to oxidation after exposure to atmosphere was studied.

2021, Borisyuk, P. V., Chubunova, E. V., Kolachevsky, N. N., Lebedinskii, Y. Y., Tkalya, E. V., Vasilyev, O. S., Yakovlev, V. P., Борисюк, Петр Викторович, Чубунова, Елена Витальевна, Лебединский, Юрий Юрьевич, Ткаля, Евгений Викторович, Васильев, Олег Станиславович, Яковлев, Валерий Петрович

An ensemble of thorium-229 ions embedded by pulsed laser implantation into a matrix of a broadband dielectric-silicon oxide is studied. The results of the experimental investigation of thorium ions' lifetime as charged components of the Th+/SiO2/Si system formed immediately after laser implantation are presented. The modelled theoretical description takes into account the instantaneous charging of the surface via laser implantation followed by charge relaxation due to the effect of autoelectronic emission that leads to time dependent partial neutralization of the surface charge by tunneling electrons. It was found that the lifetime of Th+ ions on the SiO2 surface can exceed 10 s, which would be an attractive opportunity for studying the nuclear low-lying isomeric transition in the thorium-229 isotope.

2020, Borisyuk, P. V., Vasilyev, O. S., Lebedinskii, Y. Y., Bortko, D. V., Balakhnev, K. M., Борисюк, Петр Викторович, Васильев, Олег Станиславович, Лебединский, Юрий Юрьевич, Бортко, Диана Владимировна, Балахнёв, Кирилл Максимович

© 2019 Elsevier B.V.The paper presents a study of thin Mo films, consisted of individual nanoparticles of 3.5–5.5 nm in diameter. Their chemical, electron, and optical properties are studied. It is shown that thin films consisting of individual Mo nanoparticles can be formed from the gas phase by magnetron sputtering. Atmospheric exposure leads to the formation of MoOx oxide shell around the metal nuclei of Mo nanoparticles in the films and changes in its electronic structure. Optical properties of the obtained films consisted of ‘core–shell’ Mo@MoOx nanoparticles are investigated. It is shown that the absorption window falls on the range of 190–300 nm, which can be used in the development of single-photon detectors sensitive to weak ultraviolet signals from long-live states, for example from Th-229 low-lying isomeric state.

2023, Pisarev, A. A., Tarasyuk, G. M., Borisyuk, P. V., Isaenkova, M. G., Lebedinskii, Yu. Yu., Zaripova, M. M., Исаенкова, Маргарита Геннадьевна, Писарев, Александр Александрович, Тарасюк, Григорий Михайлович, Борисюк, Петр Викторович, Лебединский, Юрий Юрьевич

Aluminum oxide layers in all its various forms have become widespread due to the unique combination of properties that can be modified by varying the conditions of their growth. The alumina layer can either be applied to the substrate by chemical and physical methods or grown by oxidation. For practical purposes, layers of various thicknesses and structures are needed. The standard method for obtaining thick (of the order of 100-1000 nm) porous layer is electric arc anodization in weak electrolytes. The standard method for obtaining thin (about 10 nm) layers is thermal oxidation. Dense layers of intermediate thickness are difficult to obtain by such methods. There are few papers in the literature that investigate the possibility of obtaining oxide layers with a thickness of tens of nanometers by oxidizing aluminum in oxygen plasma [1-5]. The description of the kinetics of the oxidation process in those works was given on the basis of the assumption of the diffusion character of oxygen transfer from the surface into the interior of the metal. This approach is absolutely unsuitable for description the transport of oxygen and aluminum through the oxide layer, since both oxygen and aluminum in the oxide are in the form of ions, and an electric charge is formed on the surface of the dielectric facing the plasma, so that the transport of oxygen coming from the plasma must occur under by the action of an electric field in the oxide dielectric layer. In this work, experiments on plasma enhanced oxidation (PEO) were carried out on the oxidation of aluminum in the anomalous glow discharge oxygen plasma, which provides uniform treatment over the entire surface of samples of arbitrary shape. Also, a simple model was proposed for description of the oxidation kinetics, taking into account oxygen transport in the electric field.

2021, Popok, V. N., Novikov, S. M., Andreev, A. A., Trunkin, I. N., Lebedinskij, Y. Y., Markeev, A. M., Лебединский, Юрий Юрьевич

© 2020, Springer Science+Business Media, LLC, part of Springer Nature.Metal nanoparticles (NPs) possessing localized surface plasmon resonance (LSPR) are of high interest for applications in optics, electronics, catalysis, and sensing. The practically important issue is the stability of the LSPR, which often limits the use of some metals due to their chemical reactivity leading to degradation of the NP functionality. In this work, copper NPs of two distinct sizes are produced by magnetron sputtering gas aggregation. This method ensures formation of the particles with high purity and monocrystallinity, enhancing the chemical inertness and providing a superior time stability of the plasmonic properties. Additionally, a simple UV-ozone treatment, which leads to the formation of an oxide shell around the copper NPs, is found to be an efficient method to prevent following gradual oxidation and assure the LSPR stability in ambient atmospheric conditions for periods over 100 days even for small (10–12 nm in diameter) NPs. The obtained results allow for significant improvement of the competitiveness of copper NPs with gold or silver nanostructures, which are traditionally used in plasmonics.

2020, Karpov, G. A., Yarotskaya, L. V., Borisyuk, P. V., Vasilyev, O. S., Efimov, V. G., Lebedinsky, Y. Y., Chubunova, E. V., Борисюк, Петр Викторович, Васильев, Олег Станиславович, Лебединский, Юрий Юрьевич, Чубунова, Елена Витальевна

© 2020, Pleiades Publishing, Ltd.Abstract: The results of a study of the local formation of thorium oxide-based coatings on the SiO2/Si (111) surface during electrochemical deposition are presented. It was experimentally found that as a result of electrochemical deposition of thorium atoms from an acetone solution of Th(NO3)4 with the presence of water on the silicon surface, local formation of thorium compounds occurs. The results of the analysis of the chemical composition of the surface by the method of local XPS analysis show that these compounds are those based on thorium, silicon, oxygen, and carbon. After annealing for 6 h at 600°C in atmosphere, carbon completely disappears, and the formed cluster film seemingly consists only of thorium and oxygen. It is shown that this system is promising for future research on nuclear low-lying isomeric transition in the 229Th isotope under electron beam irradiation.

2023, Бортко, Д. В., Борисюк, П. В., Шилов, В. А., Васильев, О. С., Лебединский, Ю. Ю., Балахнев, К. М., Балахнёв, Кирилл Максимович, Бортко, Диана Владимировна, Борисюк, Петр Викторович, Шилов, Владимир Александрович, Васильев, Олег Станиславович, Лебединский, Юрий Юрьевич

Представлены результаты формирования, аттестации морфологии поверхности и исследования оптических свойств в ближнем и среднем ИК диапазоне нанокластерных пленок Та2О5, полученных путем термического оксидирования на атмосфере монодисперсных кластерных пленок металлического тантала, созданных на подложках кремния Si(001) методом магнетронного распыления. Методами атомно-силовой микроскопии (in situ) получены изображения поверхности и показано, что пленки Ta обладают пористой плотноупакованной структурой, состоящей из отдельных наночастиц сферической формы. При помощи спектрометра на ближний и средний ИК диапазон излучения исследованы оптические свойства полученных пленок. Показано, что тонкие пленки (толщиной менее 100 нм) имеют резкую границу между областью пропускания излучения и областью поглощения и/или отражения, тогда как для более толстых пленок данный эффект постепенно исчезает с ростом толщины кластерной пленки и не зависит от размера нанокластеров. Обсуждается возможность применения полученных структур в составе термофотоэлектрогенераторов с целью повышения их КПД.

2021, Borisyuk, P. V., Vasilyev, O. S., Lebedinskii, Y. Y., Bortko, D. V., Karazhanov, S., Борисюк, Петр Викторович, Васильев, Олег Станиславович, Лебединский, Юрий Юрьевич, Бортко, Диана Владимировна, Каражанов, Смагул Жангабергенович

© 2020 Elsevier B.V.The paper presents the research of thin films, consisting of spherical monodisperse Ta particles. For different samples particle sizes varied from 1.3 nm to 5.8 nm. The films were also exposed to the atmosphere for oxidation, which resulted in formation of a core-shell particle structure, where core was metal and shell was Ta oxide (Ta2O5). Dependency of bandgap Egap and valence band offset (VBO) on particle size has been investigated for the structure by using the X-ray photoelectron spectroscopy (XPS) and reflected electron energy loss spectroscopy (REELS) methods. We have found, that Egap decreases from 4.72 eV to 4.47 eV whereas VBO decreases from 3.50 eV to 2.95 eV with increasing the particle size. A new method of a fine regulation of the electronic structure is suggested, particularly for the application in ultraviolet (UV) photodetector design for low-lying nuclear and electron transitions detection.