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Semiclassical Magnetization Dynamics and Electron Paramagnetic Resonance in Presence of Magnetic Fluctuations in Strongly Correlated Systems
Applied Magnetic Resonance. 2024. Vol. 55. P. 1091–1114.
Demishev S. V.
Semiclassical magnetization dynamics in presence of magnetic fluctuations (including the quantum ones) is derived for a strongly correlated electronic system in the region of the linear magnetic response. Landau–Lifshitz (LL) and Gilbert (G) type equations are obtained with the effective parameters depending on the type of magnetic fluctuations and their magnitude and applied to evaluation of electron paramagnetic resonance (EPR) problem in Faraday geometry. It is shown that in the studied systems LL and G equations may not be equivalent except the case of weak relaxation, where consistent Landau–Lifshitz–Gilbert (CLLG) equation may be considered. Whereas G equation is affected by quantum fluctuations solely, the LL and CLLG equations may be renormalized by magnetic fluctuations of any nature. In contrast to G equation, the LL and CLLG magnetization dynamics may be characterized by the anisotropic relaxation term caused by anisotropic magnetic fluctuations. A consequence of anisotropic relaxation is the unusual polarization effect consisting in strong dependence of the EPR line magnitude on orientation of vector h of the oscillating magnetic field with respect to the crystal structure, so that EPR may be suppressed for some directions of h. In the case of dominating quantum fluctuations, the LL and CLLG equations may lead to a universal relation between fluctuation induced contributions to the EPR line width ΔW and g-factor Δg in the form \Delta W/\Delta g = a_{0} k_{B} T/\mu_{B}, where a0 is a numerical coefficient of the order of unity and independent of the quantum fluctuation magnitude. The applicability of the proposed semiclassical magnetization dynamics models to the EPR in spin nematic phases and detection by EPR method of a new group of magnetic phenomena – spin fluctuation transitions is discussed.
Pilé I., Shchur L., Deng Y., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 114 Article 014101
We investigate the spatial overlap of successive spin configurations in Markov chain Monte Carlo simulations using the local Metropolis algorithm and the Swendsen-Wang and Wolff cluster algorithms. We examine the dynamics of these algorithms for models in different universality classes: Ising model, Potts model with three components, and four-state Potts model. The overlap of two ...
Added: July 6, 2026
МФТИ, 2025.
абота редакции научного журнала «Труды Московского физико-технического института» (кратко «Труды МФТИ»), редакционной коллегии и редакционного совета осуществляется в соответствии с Положением, утвержденным ректором института. В состав редакционной коллегии входят руководители института, факультетов, институтских и факультетских кафедр. Главный редактор журнала —президент МФТИ, член-корр. РАН Кудрявцев Н.Н.
Журнал «Труды МФТИ» входит в базу данных РИНЦ (Российский Индекс Научного Цитирования) и доступен в электронной ...
Added: July 4, 2026
Bobkov G. A., Bobkov G. A., Bobkova I. V. et al., Journal of Superconductivity and Novel Magnetism 2025 Vol. 38 Article 239
In recent years, a number of studies have predicted the emergence of a nontrivial proximity effect in superconductor/antiferromagnet (S/AF) heterostructures. This effect is of considerable interest for the efficient integration of antiferromagnetic materials into the fields of superconducting spintronics and electronics. A key element of this proximity effect is the Néel triplet correlations, initially predicted ...
Added: July 2, 2026
Bakurskiy S. V., Skryabina O. V., Ruzhickiy V. I. et al., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 113 P. 134509-1–134509-10
The miniaturization of superconducting electronics demands precise control over quasiparticle dynamics at the nanoscale. Understanding and controlling quasiparticle dynamics is essential for advancing superconducting electronics, particularly as device dimensions approach the nanoscale. Here we present direct experimental evidence for the quasiparticle-to-supercurrent conversion in planar SN-N-NS Josephson nanobridges with submicron electrodes. By employing a versatile measurement ...
Added: July 2, 2026
Polevoy K. B., Bakurskiy S. V., Ruzhickiy V. I. et al., Physical Review Applied 2026 Vol. 25 P. 024030-1–024030-12
We present a comprehensive study of planar Nb-Al-Nb Josephson junctions with submicrometer dimen sions (L ≈ 100 nm, active area of approximately 5 × 104 nm2), where the intrinsic superconductivity of the aluminum weak link plays a crucial role in enhancing device performance. Through a combi nation of theoretical modeling and experimental characterization, we demonstrate ...
Added: July 2, 2026
Никонов В. Д., Никитин С. С., Патракеев М. В., Ionics 2025 Vol. 31 No. 1 P. 675–687
Modification of perovskite-type oxides is an effective way to develop functional materials with advanced properties. The effects of cerium introduction into the A sublattice of La0.5Sr0.5FeO3−δ and variation of La:Sr ratio on the defect structure and charge transfer characteristics were studied in this work. The LaxSr0.85−xCe0.15FeO3−δ oxides were found to be single-phase with cubic (x = 0.1) and orthorhombic ...
Added: June 26, 2026
Polkin A., Skvortsov M., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 113 Article 174516
We develop a full microscopic theory for the optical conductivity 𝜎(𝜔) of a dirty current-carrying superconductor. Within the Keldysh sigma model formalism, we obtain the general analytical expression for 𝜎(𝜔), applicable for arbitrary frequency 𝜔, temperature 𝑇, and dc supercurrent 𝐼. In addition to altering the usual Mattis-Bardeen conductivity 𝜎1(𝜔), a finite supercurrent introduces two new contributions: 𝜎qp2(𝜔) from quasiparticle redistribution and 𝜎SH2(𝜔) from the amplitude ...
Added: June 25, 2026
Skvortsov M., Artem Polkin, Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 113 No. 10 Article 100502
A dissipationless supercurrent state in superconductors can be destroyed by thermal fluctuations. Thermally activated phase slips provide a finite resistance of the sample and are responsible for dark counts in superconducting single-photon detectors. The activation barrier for a phase slip is determined by a space-dependent saddle-point (instanton) configuration of the order parameter. In the one-dimensional ...
Added: June 25, 2026
Деменев А. А., Терешко С. Н., Гиппиус Н А et al., Известия РАН. Серия физическая Россия 2025 Т. 89 № 2 С. 265–273
The authors study the temporal evolution of polarized spectra of emissions from spinor exciton‒
polariton condensates in double tunnel-coupled potential traps inside a high-Q GaAs/AlAs microcavity
at 2 K upon resonance laser pumping with picosecond pulses at times of up to 1.5 ns. The period of the condensates’
spin relaxation in a double trap is estimated as τs ...
Added: June 23, 2026
Абрамов-Максимов В. Е., И.А. Бакунина, Геомагнетизм и аэрономия 2026 Т. 66 № 3 С. 515–529
Проанализировано 8 вспышечных событий по данным многочастотных наблюдений сети радиотелескопов Radio Solar Telescope Network. Целью анализа было выявление предвестников солнечных вспышек. В семи рассмотренных случаях выявлены предвспышечные квазипериодические флуктуации радиоизлучения. Сделанная по вейвлет-спектрам оценка квазипериодов дает в большинстве случаев значения 40–50 сек. В одном событии с большой вспышкой класса M8.0 квазипериодические флуктуации не проявились. В ...
Added: June 22, 2026
И.А. Бакунина, В.Ф. М., А.В. Ш. et al., Геомагнетизм и аэрономия 2025 Т. 65 № 9 С. 1363–1373
Рассмотрена связь особенностей положения и ориентации магнитных жгутов в активной области (АО) с источниками микроволнового (17 ГГц) излучения и излучения в крайнем ультрафиолетовом диапазоне (EUV) при возникновении эруптивных вспышек, сопровождающихся корональными выбросами массы, и вспышек с "запертой" эрупцией. Приведены примеры эруптивных событий, демонстрирующие пространственное совпадение микроволновых источников с расположением магнитных жгутов в АО, восстановленных при ...
Added: June 22, 2026
Г. Г. Бондаренко, Кристя В. И., Савичкин Д. О. et al., Поверхность. Рентгеновские, синхротронные и нейтронные исследования 2026 № 4 С. 29–36
Сформулирована модель тлеющего газового разряда в смеси аргона и паров ртути при наличии
на поверхности катода тонкой диэлектрической пленки. Рассчитаны зависимости характеристик
разряда от температуры в интервале ее изменения, в котором заметный вклад в ионизацию
рабочей газовой смеси дает ионизация атомов ртути метастабильными возбужденными атомами
аргона (реакция Пеннинга). Показано, что в случае катода без диэлектрической пленки при
повышении температуры до ...
Added: June 20, 2026
Chertenkov V. I., Shchur L., Lobachevskii Journal of Mathematics 2026 Vol. 47 No. 2 P. 720–727
Supervised machine learning is successfully applied to the study of critical phenomena and allows us to obtain a numerical estimate of the phase transition temperature and the correlation length exponent. We discuss the influence of possible systematic errors, as well as statistical errors, on the accuracy of such numerical estimates. Errors in the training and ...
Added: June 16, 2026
Батурин А. С., Гаврилов В. Р., Иванов А. В. et al., Измерительная техника 2026 Т. 75 № 2 С. 14–28
28 декабря 2025 года Всероссийскому научно-исследовательскому институту оптико-физических измерений (ВНИИОФИ) исполнилось 60 лет. За прошедшие десятилетия институт выполнил значительное количество научных исследований, разработал и поставил потребителям тысячи высокоточных средств оптико-физических измерений (включая эталонное оборудование). В статье представлены наиболее значимые для метрологического обеспечения оптико-физических измерений результаты научно-исследовательских работ, выполненных ВНИИОФИ за период 2016–2025 гг. ...
Added: June 15, 2026
Вишняков Г. Н., Левина Э. Ю., Minaev V., Измерительная техника 2025 Т. 74 № 2 С. 20–27
Качество формируемого оптической системой изображения определяется её частотно-контрастной характеристикой или коэффициентами передачи модуляции на различных пространственных частотах. Для обеспечения единства измерений коэффициентов передачи модуляции и создания эталонной базы по воспроизведению, хранению и передаче единицы коэффициента передачи модуляции усовершенствован Государственный первичный эталон единиц оптической силы очковой оптики ГЭТ 205-2013 в части воспроизведения единицы коэффициентов передачи модуляции ...
Added: June 15, 2026
Filippova A. V., Yurchenko N. Y., Smirnov S. A. et al., Journal of Alloys and Compounds 2026 No. 1074 Article 189162
This study investigates the effects of post-processing heat treatment at 300–500 °C on the microstructure, hardness, and tensile properties of laser powder bed fusion (PBF-LB) processed Al-bronze processed with energy densities (ED) in the range of 125–938 J/mm3. In the as-printed state, sharp needle-like α + β′ laths form at lower ED whereas with increasing ED, the β′ ...
Added: June 12, 2026
Спонтанное образование скин-слоя в воде с деформацией ОН-полосы КР вкладом компоненты льда 3200 см-1
Першин С. М., Степанов Е. В., Артемова Д. Г. et al., Письма в Журнал экспериментальной и теоретической физики 2026 Т. 123 № 6 С. 383–390
Открыто спонтанное образование в течение 4 ч скин-слоя дистиллированной воды толщиной до 3 мм при комнатной температуре с новыми свойствами. Обнаружены деформация ОН-полосы комбинационного рассеяния вкладом компоненты льда ( 3200 см-1), снижение коэффициента упругого рассеяния и его флуктуаций, а также увеличение на 20 капиллярах. Восстановление слоя после обогащения воздухом в результате перемешивания указывает на стабильность ...
Added: June 8, 2026
Murzakhanov F., Forysenkova Anna A., Fadeeva I. et al., Ceramics 2022 Vol. 5 No. 3 P. 318–329
Powders of β-tricalcium phosphate (β-TCP, Ca3PO4) doped with manganese (Mn2+) are comprehensively analyzed with electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) techniques. The modeling of the spectra permitted to calculate the values of zero-field splitting (𝐵02 = −904 MHz; 𝐵04 = −1.41 MHz and 𝐵34 = 195.2 MHz) and explain the origin of the low-field hyperfine structures as ...
Added: August 12, 2025
Forysenkova Anna A., Ivanova V., Fadeeva I. et al., Materials 2023 Vol. 16 No. 7 P. 2832–2843
Alginate is a natural polymer widely applied in materials science, medicine, and biotechnology. Its ability to bind metal ions in order to form insoluble gels has been comprehensively used to create capsules for cell technology, drug delivery, biomedical materials, etc. To modify and predict the properties of cross-linked alginate, knowledge about the mechanism of alginate ...
Added: August 12, 2025
Sadovnikova M., Murzakhanov F., Fadeeva I. et al., Ceramics 2022 Vol. 5 No. 4 P. 1154–1166
Tricalcium phosphate (TCP)-based materials, such as β-Ca3(PO4)2 doped with rare earth ions (RE), have shown applications as biomaterials, lighting emitting materials, scintillating materials, in vivo imaging probes, and thermoluminescent dosimeters. Their properties are found to be dependent on the distribution of RE3+ on Ca2+ sites that can be controlled by pulsed electron paramagnetic resonance (EPR) and electron spin ...
Added: August 12, 2025
S. K. Gotovko, Ivanova A. G., P. S. Kudimkina et al., Physical Review B: Condensed Matter and Materials Physics 2025 Vol. 111 No. 6 Article 064430
We present the study of low-frequency dynamics of LiCu3O3—an antiferromagnet on a strongly depleted square lattice. The crystal structure contains two types of square planes with different Li+→Cu2+ substitution rates (20% and 40%). Recent nuclear magnetic resonance (NMR), magnetization measurements and neutron scattering experiments revealed the occurrence of antiferromagnetic order at 𝑇𝑐1=123K and the change ...
Added: March 3, 2025
S. V. Demishev, Shestakov A. V., Yatsyk I. V. et al., Solid State Communications 2024 Vol. 385 Article 115501
In the spiral conical phase of manganese monosilicide, MnSi, the EPR spectra are studied at a frequency of 9.3
GHz in the temperature range of 5–30 K for an external magnetic field oriented along the crystallographic di
rection [100]. It is found that in the temperature range T < T* = 25 K, located 4 K below ...
Added: February 9, 2025
Sosin S., Яфарова А. Ф., Романова И. В. et al., Письма в Журнал экспериментальной и теоретической физики 2022 Т. 116 № 11-12 С. 747–755
Low-temperature electron paramagnetic resonance measurements are performed on single crystals of LiY1 – xGdxF4 with low x = 0.005 and moderate x = 0.05 concentration of Gd ions. Modeling of the experimental spectra allows us to precisely determine microscopic parameters of the spin Hamiltonian of the parent LiGdF4 material, including the nearest-neighbor exchange constant. The obtained parameters ...
Added: December 7, 2022
Demishev S. V., Doklady Physics 2021 Vol. 66 No. 7 P. 187–190
The Landau–Lifshitz equation modified by quantum fluctuations of the magnetic moment is proposed, on the basis of which several new effects in electron paramagnetic resonance in strongly correlated electronic systems are predicted, including an increase in the integral intensity and the appearance of universal relations connecting the contribution to the linewidth, the shift of the ...
Added: October 25, 2022