2304-9782, 2618-8686, 2405-7223 19 1 2026 1-193

RAR RUS 9-18 0000-0001-8973-3187 Alferov University Shugurov Konstantin 0000-0002-8661-4083 Alferov University Mozharov Alexey mozharov@spbau.ru

St. Petersburg, Russian Federation

0000-0002-3640-677X Ioffe Institute Kaveev Andrey kaveev@mail.ioffe.ru

St. Petersburg, Russian Federation

0000-0001-5547-9387 Alferov University Fedorov Vladimir fedorov_vv@spbstu.ru The resistive switching effect in the n-GaN/p-Si heterostructures In the paper, the findings of study the memristor based on n-GaN nanowires synthesized on silicon by the molecular beam epitaxy with SiN and AlN interface layers have been presented. The polarity inversion of writing voltage was found to depend on the interface preparation method. In addition, it was discovered by the capacitive measurements that after the logical state write operation, the structure capacitance decreased when using the SiN layer while it increased when using the AlN one. In this case, a difference was observed in the behavior of the subsequent relaxation of the capacitance. 10.18721/JPM.19101 537.9 gallium nitride nanowire memristor effect resistive switching silicon hydrogen passivation https://physmath.spbstu.ru/article/2026.86.1/ 01_9-18_19(1)2026.pdf

RAR RUS 19-29 0000-0002-5474-5281 Amur State University Fomin Dmitriy e-office@yandex.ru 0009-0004-6651-1468 Sholygin Ilya ilia.sholygin235@bk.ru

Amur State University

0009-0009-5104-5966 Amur State University Polyakov Aleksey polyakov_a_1999@mail.ru 0000-0003-4127-2988 Institute of Automation and Control Processes, Far Eastern Branch of the RAS Galkin Nikolay galkin@iacp.dvo.ru 0000-0001-5386-1013 Institute of Automation and Control Processes, Far Eastern Branch of the RAS Galkin Konstantin galkinkn@iacp.dvo.ru 0000-0002-8726-9832 Institute of Automation and Control Processes, Far Eastern Branch of the RAS Chernev Igor igor_chernev7@mail.ru Photoelectric properties of diodes based on magnesium silicide semiconductor In this work, an indirect-gap semiconductor Mg2Si has been synthesized and studied. Mg2Si was formed as a 682 nm thick polycrystalline film (the formation was established using Raman scattering and Fourier-transform IR spectroscopies). X-ray phase analysis revealed that the Mg2Si (220) crystallographic direction in the sample was predominant. Based on the Hall effect measurements, the electronic type of the film conductivity was proven. Photodiode structures with Al/Mg2Si/Si-n/Au-Sb and Au/Mg2Si/Si-n/Au-Sb p–n junctions were made from the film. Their current-voltage characteristics were measured and analyzed. The dependences of the structure photoresponse on the radiation wavelength, the sign and magnitude of the applied potential were established, and their features were identified. An analysis of the obtained experimental data showed that a double p–n junction with a barrier layer was forming in the high-temperature annealing of silicon. This junction, together with the Mg2Si/Si-p heterojunction, determined the unique photospectral characteristics of the system. 10.18721/JPM.19102 621.315.592+621.383.522 magnesium silicide photodiode heterostructure p–n junction local photoresponse photospectral characteristic https://physmath.spbstu.ru/article/2026.86.2/ 02_19-29_19(1)2026.pdf

RAR RUS 30-42 0000-0002-5226-1101 Research Institute of Semiconductor Physics and Microelectronics at the National University of Uzbekistan named after Mirzo Ulugbek Ataboev Omonboy 0000-0002-1718-1122 Research Institute of Semiconductor Physics and Microelectronics at the National University of Uzbekistan named after Mirzo Ulugbek Utamuradova Sharifa 0000-0002-5226-1101 Ioffe Institute Terukov Evgenyi eug.terukov@mail.ioffe.ru

St. Petersburg, Russian Federation

0000-0002-4894-6503 Alferov University Baranov Artem I. baranov_art@spbau.ru

St. Petersburg, Russian Federation

Nukus State Technical University Iniyatova Klara klarainiyatova2002@gmail.com Temperature effects on the light current-voltage characteristics of the heterojunction solar cells fabricated on gallium-doped silicon substrates In this study, the impacts of temperature on the light current-voltage characteristics of heterojunction solar cells fabricated on gallium-doped crystalline p-type silicon (c-Si) has been studied under air mass zero spectrum (136.7 mW/сm²) in the temperature range from 173 to 373 K. Our experimental results indicated that the short-circuit current density increased linearly with temperature, exhibiting a positive temperature coefficient of 0.058%/K, whereas the open-circuit voltage (Vос) decreased linearly. From the experiment, the calculated temperature coefficient value of the Vос was found to be −0.182%/K. Both the maximum output power and conversion efficiency of the heterojunction solar cells increased linearly with decreasing temperature from 373 K, reaching peak values of ~29.5 mW/cm² and ~21.5% at 173 K. The temperature coefficient of the maximum output power was evaluated to be −0.2%/K, which represents one of the record-breaking small values reported among SCs based on other single c-Si technologies. 10.18721/JPM.19103 620.92; 539.232; 538.9; 535.215.6 heterojunction solar cell temperature dependence open-circuit voltage conversion efficiency temperature coefficient https://physmath.spbstu.ru/article/2026.86.3/ 03_30-42_19(1)2026.pdf

RAR RUS 43-61 0000-0003-0542-0939 Gomel State Technical University named after P. O. Sukhoi Kiselevich Valentin

48 October Ave., Gomel, 246029, Republic of Belarus

Application of the catastrophe theory to describe temperature dependencies of the breakdown field strength in polymer dielectrics An equation expressing the dependence of the breakdown field strength of polymer dielectrics on ambient temperature has been derived based on the hypothesis of an analogy between the physical phenomenon of breakdown and the mathematical cusp catastrophe. The parameters of this equation were determined, and temperature dependencies of breakdown field strength for polyethylene terephthalate, atactic polypropylene, and polybutadiene were constructed. А high degree of correlation between the published experimental data and the calculated temperature dependencies corresponding to the obtained equation was demonstrated. A good agreement between the characteristic glass transition temperatures and electrical breakdown temperatures for all polymers taken was shown. Our work puts forward a hypothesis suggesting a correlation between the kinetic processes of glass transition and electrical breakdown in these polymers. 10.18721/JPM.19104 621.315.61: 51-74 polymer dielectric electrical breakdown breakdown field strength glass transition temperature catastrophe theory cusp catastrophe https://physmath.spbstu.ru/article/2026.86.4/ 04_43-61_19(1)2026.pdf

RAR RUS 62-69 0009-0002-3569-4981 Herzen State Pedagogical University of Russia Kulemina Sofya Herzen State Pedagogical University of Russia Temnov Dmitry tde@herzen.spb.ru Thermally stimulated relaxation of surface potential in polylactide-based composite films The stability of the electret state in polylactide films with a white soot dispersed filler has been studied using the method of thermally stimulated relaxation of the surface potential. The best electret properties were shown to exhibit by the films with a filler content of at least 4%, and the films polarized in a negative corona discharge field. The parameter values of the relaxation processes (the activation energy value and effective frequency factor one) responsible for the electret state of this material were found by numerical simulation. The relaxation time of the electret state at room temperature was determined for the samples under study. The obtained results allow us to recommend the composites as an active packaging material. 10.18721/JPM.19105 538.915 electret state thermally stimulated relaxation of surface potential polylactide dispersed filler https://physmath.spbstu.ru/article/2026.86.5/ 05_62-69_19(1)2026.pdf

RAR RUS 70-82 Peter the Great St. Petersburg Polytechnic University Ageev Daniil ageev2de@gmail.com Peter the Great St. Petersburg Polytechnic University Zasimova Marina zasimova_ma@spbstu.ru A natural convection airflow and its heat transfer around a single horizontal finned tube The paper presents the results of numerical investigation of a natural convective airflow and its heat transfer forming around a single horizontal finned tube (the ratio of a fin diameter to the base tube one is 2.15). Calculations have been carried out at a Rayleigh number Ra = 2×107 or less. Variation of the Ra value was achieved by changing the temperature difference between the heated tube surface and the ambient air, as well as by modifying the geometric scale of the problem. The fin spacing-to-the base tube diameter ratio was varied in the range from 0.09 to 0.55. The optimal fin spacing of 0.23 was determined, corresponding to the maximum heat removal from the taken tube. Good agreement was shown between the calculated results and available experimental data from the literature. 10.18721/JPM.19106 532.517 natural convection heat transfer finned tube numerical investigation Rayleigh number https://physmath.spbstu.ru/article/2026.86.6/ 06_70-82_19(1)2026.pdf

SCO RUS 83-90 0000-0001-8440-494X Alferov University Novikova Kristina novikova_k@spbau.ru

St. Petersburg, Russian Federation

0009-0000-3147-6974 Alferov University of RAS Funtikova Anastasiia 0000-0002-8661-4083 Alferov University Mozharov Alexey mozharov@spbau.ru

St. Petersburg, Russian Federation

0000-0001-9792-045X Peter the Great St. Petersburg Polytechnic University Mukhin Ivan muhin_is@spbstu.ru Numerical study of the light extraction efficiency from gallium phosphide nanowires integrated with a gold nanoparticle In order to develop the fabrication technology of GaP nanowires (NWs) integrated with Au nanoparticles (NPs), i.e., of an object promising for creating red-range micro-LEDs, its light extraction efficiency has been analyzed both with and without the Au NP. Moreover, the relationship between this efficiency and the position of the active region within the core-shell LED heterostructure was investigated. In this case the full-wave optical numerical simulation of light propagation using the "COMSOL Multiphysics" software package, specifically the "Wave Optics" module, was performed. The system under study included a silicon substrate in the aerial environment with the object (GaP NW + Au NP) clamped to. An imitation of an optical point dipole was taken as a radiation source. The presence of the Au nanoparticle was shown to lead to a significant increase (of approximately 12%) in light extraction efficiency due to localized surface plasmon resonance and the enhancement of the near electric field in the contact area of the Au particle with the nanocrystal. 10.18721/JPM.19107 535.3, 004.353.254.5 gallium phosphide GaAsPN gold nanoparticle hybrid nanostructure light extraction efficiency https://physmath.spbstu.ru/article/2026.86.7/ 07_83-90_19(1)2026.pdf

RAR RUS 91-105 University of Thi-Qar, Department of Physics, College of Science Khalaf Rihab rihab.khalaf@utq.edu.iq

University of Thi-Qar 362C+65R, An Nasiriyah, Thi-Qar Governorate, 64001, Republic of Iraq

0009-0003-4737-7008 University of Thi-Qar, Department of Physics, College of Science Jabbar Mohammed mohammed25382@gmail.com Size-dependent adsorption and electronic modulation of pyrene nanostructures toward toxic gas detection: a DFT study The DFT-study at the B3LYP/6-31G level has been conducted to analyze the interactions of pyrene-based graphene fragments with toxic gases F2, AsH3, PH3, and HF. Three diamond-shaped n-pyrene clusters (n = 3, C30H14; n = 4, C48H18; n = 5, C70H22) were systematically optimized, and their adsorption behavior was investigated through the total and adsorption energies, frontier molecular orbital (HOMO – LUMO) distributions, and energy gaps. The results revealed that gas adsorption induces significant modifications in the electronic structure of the pyrene clusters, with variations depending on both the cluster size and gas nature. The calculated adsorption energies demonstrated a size-dependent trend, indicating that increasing the number of zigzag edges in pyrene enhances surface reactivity toward certain analytes. These findings highlight the potential of pyrene-based graphene nanostructures as selective and efficient sensors for hazardous gases. 10.18721/JPM.19108 536.423 graphene pyrene toxic gas adsorption DFT cluster size molecular orbital energy gap gas detection https://physmath.spbstu.ru/article/2026.86.8/ 08_91-105_19(1)2026.pdf

RAR RUS 106-120 0000-0001-9446-4233 Peter the Great St. Petersburg Polytechnic University Valuyeva Svetlana

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0000-0003-3068-7838 Institute of Macromolecular Compounds – Branch of Petersburg Nuclear Physics Institute named by B. P. Konstantinov of National Research Centre “Kurchatov Institute” Morozova Polina 0000-0002-4334-7595 Institute of Macromolecular Compounds – Branch of Petersburg Nuclear Physics Institute named by B. P. Konstantinov of National Research Centre “Kurchatov Institute” Vylegzhanina Milana 0009-0006-3914-2307 Institute of Macromolecular Compounds – Branch of Petersburg Nuclear Physics Institute named by B. P. Konstantinov of National Research Centre “Kurchatov Institute” Chernova Lyudmila 0000-0002-1034-6713 Institute of Macromolecular Compounds – Branch of Petersburg Nuclear Physics Institute named by B. P. Konstantinov of National Research Centre “Kurchatov Institute" Borovikova Lyudmila The photodegradation of the free and bound Radachlorin solutions: A comparative study The comparative photodegradation studies of a free photosensitizer Radachlorine and Radachlorine being a part of the triple selenium-containing nanosystem (PS-2) based on the amphiphilic molecular brush (AMB) with a cellulose backbone and side chains of polymethacrylic acid (bound Radachlorine) have been performed using UV/visible spectroscopy, atomic force microscopy, and luminescence. The effect of the light exposure time on the optical density and luminescence intensity of Radachlorine in both states was established. The AMBs were found to hinder the association of selenium nanoparticles in the solution forming discrete spherical nanostructures before irradiation. But the nanostructures acquired an ellipsoidal shape after 60 min exposure; in addition, there was a tendency towards their association. On the basis of the UV/visible spectroscopy data for the PS-2 obtained before and after irradiation, the values of the band gap energy and diameter of the selenium nanoparticles were calculated. 10.18721/JPM.19109 541.64:544.77:532.77:620.186 selenium-containing nanosystem Radachlorine photodegradation nanoparticle nanostructure morphology band gap energy https://physmath.spbstu.ru/article/2026.86.9/ 09_106-120_19(1)2026.pdf

RAR RUS 121-132 Peter the Great St. Petersburg Polytechnic University Anisimov Andrey anisimov.spbstu@yandex.ru 0000-0003-0617-4514 Peter the Great St. Petersburg Polytechnic University Belov Andrey belov@spbstu.ru 0000-0002-1722-1964 Peter the Great St. Petersburg Polytechnic University Kozlov Artemy kozlov_as@spbstu.ru 0000-0001-8448-2024 Peter the Great St. Petersburg Polytechnic University Kotov Oleg kotov@rphf.spbstu.ru 0009-0003-4426-9503 Peter the Great St. Petersburg Polytechnic University Krinskiy Pavel 0000-0001-7083-9184 Peter the Great St. Petersburg Polytechnic University Medvedev Andrei medvedev@spbstu.ru 0000-0001-5216-6588 Peter the Great St. Petersburg Polytechnic University Petrov Aleksandr petrov.av1@spbstu.ru Peter the Great St. Petersburg Polytechnic University Rozov Sergey svroz@yandex.ru Peter the Great St. Petersburg Polytechnic University Ushakov Nikolai n.ushakoff@spbstu.ru Measurement of the timing jitter of a low-noise single photon detector The article puts forward a technique for measuring the time jitter of a single photon detector (SPD). The proposed method does not require high-speed electronics and short optical pulses. The procedure involves experimental measurement of the time delays of the SPD response to short weak optical pulses of variable duration applied to its input. In this case, the optical pulse duration may exceed the measured jitter value. The results of measuring the time jitter of a low-noise SPD using an avalanche photodiode (manufactured by RMY Electronics) have been presented and compared with a commercially available ID Quantique IDQube-NIR-GAT-MMF-LN detector. Our experimental studies have proved the success of the proposed time jitter measurement technique. 10.18721/JPM.19110 535.14 single photon detector avalanche photodiode quantum key distribution timing jitter https://physmath.spbstu.ru/article/2026.86.10/ 10_121-132_19(1)2026.pdf

RAR RUS 133-143 0000-0001-8750-038X Samarkand State University Kuvandikov Oblakul quvandikov@rambler.ru 0009-0000-8607-813X Samarkand State University Shodiev Zokir shodiyevzm@gmail.com 0009-0007-7082-9251 Samarkand State University Akhtamov Jushkin texnalogiya11@gmail.com Electronic and magnetic properties of hausmannite In this work, the magnetic and electronic properties of the mineral hausmannite (Mn3O4) have been studied using both experimental and theoretical methods. Magnetic susceptibility χ was measured in the paramagnetic region over the temperature range of 288–1000 K using the Faraday method. The anomalies recorded at 657 K and 898 K in the χ⁻¹(T) plots were attributed to the Jahn–Teller effect, and this phenomenon was also found in the differential scanning calorimetry (DSC) analysis. Using the first-principles calculations based on the DFT+U method within the Quantum ESPRESSO package, the magnetic moment values of –4.1113 and 3.4801 Bohr magnetons (μB) for Mn2+ and Mn3+ ions, respectively, were obtained. The result of a net magnetization of 6.00 μB per cell was established which indicated the ferrimagnetic nature of the object. Band structure analysis confirmed the semiconductor nature of hausmannite (a theoretical band gap Eg ≈ 0,82 eV). 10.18721/JPM.19111 537.6:548.73:538.91 hausmannite magnetic susceptibility DSC Curie – Weiss law Jahn – Teller effect https://physmath.spbstu.ru/article/2026.86.11/ 11_133-143_19(1)2026.pdf

RAR RUS 144-157 Peter the Great St. Petersburg Polytechnic University Bannikov Egor bannikov.ev.21@gmail.com 0000-0003-0309-5917 Peter the Great St. Petersburg Polytechnic University Berdnikov Yaroslav berdnikov@spbstu.ru 0000-0002-3395-0454 Peter the Great St. Petersburg Polytechnic University Kotov Dmitry dmitriy.kotov@gmail.com Peter the Great St. Petersburg Polytechnic University Larionova Dariya dlar@bk.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

Comparison of elliptic flows of π0 mesons in Cu + Au collisions at 200 GeV and U + U collisions at 193 GeV This paper presents the findings of investigation of the elliptic flows of π0 mesons as functions of transverse momentum for different centrality classes of relativistic nuclei Cu + Au collisions at an energy of 200 GeV and U + U collisions at 193 GeV. A comparison of the obtained values is also presented. The results of the comparison have been indicated that a larger volume of quark-gluon plasma formed in the U + U collisions. Moreover, the elliptic flows of π0 mesons were established to have positive values at transverse momenta up to 10 GeV/c in the collision systems under study. Thus, the results obtained on elliptic flows allow us to further study the dependences of parton energy losses on their path lengths in the quark-gluon plasma forming in the Cu + Au and U + U collisions. 10.18721/JPM.19112 539.12 quark-gluon plasma azimuthal anisotropy elliptic flow π0 mesons https://physmath.spbstu.ru/article/2026.86.12/ 12_144-157_19(1)2026.pdf

RAR RUS 158-169 0000-0003-1457-8236 Peter the Great St. Petersburg Polytechnic University Ipatov Andrey andrei_ipatov@mail.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0009-0001-5775-2276 Peter the Great St. Petersburg Polytechnic University Kupriianov Genrikh henryweis3@gmail.com Dependence of optical spectra of bulk-doped cadmium sulfide semiconductor nanocrystals on their geometrical dimensions and number of charge carriers The theoretical study of dipole plasmon resonances in bulk-doped CdS semiconductor nanocrystals has been continued. In this paper, the case of a larger number of free carriers in a nanocrystal was considered. It was demonstrated that the giant dipole resonance dominated in the photoabsorption spectra of the systems considered. For this case, all the trends and dependencies revealed earlier were established to remain the same. Thus, the character of the collective mode can change from the classical dipole plasmon regime to the size quantization one when varying the height of the potential barrier at the nanoparticle boundary. In so doing, the character and rate of this change depend on the number of free carriers and the nanocrystal size. 10.18721/JPM.19113 538.9 semiconductor nanocrystal cadmium sulfide doping plasmon resonance multiparticle excitation https://physmath.spbstu.ru/article/2026.86.13/ 13_158-169_19(1)2026.pdf

RAR RUS 170-190 0000-0003-2016-8612 Peter the Great St. Petersburg Polytechnic University Lukin Alexei lukin_av@spbstu.ru

Russian Federation, 195251, St. Petersburg, Polytechnicheskaya, 29

0000-0003-4425-9172 Peter the Great St. Petersburg Polytechnic University Popov Ivan popov_ia@spbstu.ru Peter the Great St. Petersburg Polytechnic University Piskun Nikita piskun_nd@spbstu.ru 0009-0000-6354-9621 Peter the Great St. Petersburg Polytechnic University Antufiev Denis antufiev_dv@spbstu.ru Nonlinear reduced order models for elastic structures The problem of synthesizing the reduced-order dynamic models for continuous elastic systems in a geometrically nonlinear formulation (primarily thin-walled structures) based on the finite element method is considered. The approaches under consideration are based on the idea of identifying the nonlinear (quadratic-cubic) stiffness characteristic of an elastic system in its modal coordinates, followed by the application of the theory of nonlinear normal modes and Poincaré normal forms to construct an invariant manifold tangent to the selected modal subspace. The developed algorithm is used to construct a nonlinear model of coupled longitudinal-bending vibrations of a clamped-clamped beam and its verification based on an approximate analytical solution by the Galerkin method. The features of the software implementation of the presented method based on the ABAQUS finite element analysis software system are discussed. 10.18721/JPM.19114 534-13 nonlinear theory of elasticity Poincaré normal form nonlinear modal interaction reduced-order model https://physmath.spbstu.ru/article/2026.86.14/ 14_170-190_19(1)2026.pdf