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12th edition of MSM conference continued the series of meetings started in 1999 as an international conference with the objective of strengthening scientific relations among the scientific groups in the middle eastern region and with the advanced world scientific community. Since then the MSM meetings became a biennial event held in Asia, Africa and Europe, finally reaching the heart of western Europe, Duisburg, in 2022. The program of MSM22 included a broad range of plenary, invited and contributed (oral & poster) presentations and covered latest advances in fundamental and applied magnetism and superconductivity as well as many related topics.

Motivated by the recent advances in modelling the pseudo-Hermitian Hamiltonian (pHH) systems using superconducting qubits we analyze their quantum dynamics subject to a small time-dependent perturbation. In particular, We develop the linear response theory formulation suitable for application to various pHH systems and compare it to the ones available in the literature. We derive analytical expressions for the generalized temporal quantum-mechanical correlation function $C(t)$ and the time-dependent dynamic susceptibility $\chi(t) \propto \text{Im} ~C(t)$. We apply our results to two \textit{PT}-symmetric non-Hermitian quantum systems: a single qubit and two unbiased/biased qubits coupled by the exchange interaction. For both systems we obtain the eigenvalues and eigenfunctions of the Hamiltonian, identify \textit{PT}-symmetry unbroken and broken quantum phases and quantum phase transitions between them. The temporal oscillations of the dynamic susceptibility of the qubits polarization ($z$-projection of the total spin), $\chi(t)$, relate to {\it ac} induced transitions between different eigenstates and we analyze the dependencies of the oscillations frequency and the amplitude on the gain/loss parameter $\gamma$ and the interaction strength $g$. Studying the time dependence of $\chi(t)$ we observe different types of oscillations, i.e. undamped, heavily damped and amplified ones, related to the transitions between eigenstates with broken (unbroken) $PT$-symmetry. These predictions can be verified in the microwave transmission experiments allowing controlled simulation of the pHH systems., Comment: 11 pages, 6 figures, published version

Recent advances in the field of THz spectroscopy allow for controlled experiments to measure signatures of collective excitations in the conventional s-wave superconductor in the fifth harmonic generation current (FHG). Here, we analyze this process theoretically within the Anderson pseudospin formalism and use a periodic multicycle pulse setup, where the driving electromagnetic field points in the direction of a lattice vector. We investigate the interplay of the Higgs mode contribution to the fifth harmonic generation current and compare it to other contributing mechanisms, such as charge density fluctuations (CDF). Similar to the third harmonic generating current we show that the signal in the FHG is also dominated by the CDF. Most importantly, we predict a double peak signature in the frequency dependence of the intensity amplitude of the FHG current with one peak located at

We analyze theoretically the influence of domain walls (DWs) on the DC Josephson current in magnetic superconducting S$_{m}$/Fl/F/Fl/S$_{m}$ junctions. The Josephson junction consists of two "magnetic" superconductors S$_{m}$ (superconducting film covered by a thin ferromagnetic layer), spin filters Fl and a ferromagnetic layer F with or without DW (DWs). The spin filters Fl allow electrons to pass with one specific spin orientation, such that the Josephson coupling is governed by a fully polarized long-range triplet component. In the absence of DW(s), the Josephson and spin currents are nonzero when the right and left filters, Fl$_{r,l}$, pass electrons with equal spin orientation and differ only by a temperature-independent factor. They become zero when the \textbf{spins} of the triplet Cooper pairs passing through the Fl$_{r,l}$ have opposite directions. Furthermore, for the different chiralities of the injected triplet Cooper pairs the spontaneous currents arise in the junction yielding a diode effect. Once a DW is introduced, it reduces the critical Josephson current $I_{c}$ in the case of equal spin polarization and makes it finite in the case of opposite spin orientation. The critical current $I_{c}$ is maximal when the DW is in the center of the F film. A deviation of the DW from the center generates a force that pushes the DW to the center of the F film. In addition, we consider the case of an arbitrary number $N$ of DW's, with the case $N=2$ corresponding to a model system for a magnetic skyrmion., Comment: 13 pages, 3 figures

In cuprate superconductors, due to strong electronic correlations, there are multiple intertwined orders which either coexist or compete with superconductivity. Among them, the antiferromagnetic (AF) order is the most prominent one. In the region where superconductivity sets in, the long-range AF order is destroyed. Yet the residual short-range AF spin fluctuations are present up to a much higher doping, and their role in the emergence of the superconducting phase is still highly debated. Here, by using a spin-polarized scanning tunneling microscope, we directly visualize an emergent incommensurate AF order in the nearby region of Fe impurities embedded in the optimally doped Bi(2)Sr(2)CaCu(2)O(8+δ) (Bi2212). Remarkably, the Fe impurities suppress the superconducting coherence peaks with the gapped feature intact, but pin down the ubiquitous short-range incommensurate AF order. Our work shows an intimate relation between antiferromagnetism and superconductivity.

Рассмотрены основные операции с данными при автоматизированной обработке записи летного эксперимента. Оценена актуальность создания новой программной среды обработки данных и определены требования к ней. Показаны результаты разработки демонстрационной программы с ограниченным набором функций.

Рассмотрены общие характеристики файлов, получаемых по результатам первичной обработки полетной информации. Определены особенности представления данных в форме таблиц, влияющие на считывание содержимого таблицы из файла. Представлен программный код модуля считывания данных из файла, подтвердивший работоспособность в динамическом тестировании. Определены направления доводки модуля до полноценной практической применимости.

Using the method of molecular dynamics and taking Ni3Al and Pt3Al as examples, crystals of the A3B composition are considered for the possibility of excitation of soliton-type waves in them. The potentials obtained by the embedded-atom method were used to describe interatomic interactions. It is shown that the harmonic external stimulus can excite waves of the soliton type in a Pt3Al crystal, but not in Ni3Al. Such compression–expansion waves are generated because of excitation of discrete breathers with soft nonlinearity that cannot exist in a Ni3Al crystal near the affected region. The detected waves are capable of propagating to thousands of nanometers along the Pt3Al crystal without losses of integrity and speed. The shape of the obtained wave corresponds to the kink solution of the sine-Gordon equation. The aggregate amount of energy transferred by a wave is determined by the number of rows of atoms involved in fluctuations; this may involve dozens and hundreds of electron volts.

The effect of the nonlinear supratransmission in crystal of A3B stoichiometry is studied by molecular dynamics on the example of Pt3Al alloy. This effect is the transfer of energy at frequencies outside the phonon spectrum of the crystal. Research of the mechanisms of energy transport from the material surface to the interior is the important task, both from the theoretical point of view and from the prospects for practical application in the modification of near-surface layers by treatment with intense external influence of various types. The model was a three-dimensional face-centered cubic crystal whose atoms interact by means of the multiparticle potential obtained by the embedded atom method, which provides greater realism of the model in comparison with the use of pair potentials. Various forms of oscillation of the external influence region are considered. The possibility of energy transport from the crystal surface to the interior is shown by excitation of quasi-breathers near the region of influence and their subsequent destruction in the crystal and scattering of the energy stored on them. The quasibreathers are high-amplitude nonlinear atoms' oscillations of the alloy lightweight component at frequencies outside the phonon spectrum of the crystal. This effect was observed not with every oscillation's form of the region of influence. Quasi-breathers appeared most intensely near the region of influence with sinusoidal form oscillations. The results obtained indicate that the contribution of quasi-breathers to the energy transfer through the crystal increases with increasing amplitude of the influence. The range of amplitudes from 0.05 to 0.5 Å is considered. The frequency of the influence varied from 0.2 to 15 THz, which ensured the coverage of the entire spectrum of lowamplitude oscillations for this crystal's model. The minimum magnitude of the external effect amplitude at which this effect was observed was found to be 0.15 Å. At amplitudes greater than 0.5 Å, the cell rapidly decays for frequencies close to the optical branch of the phonon spectrum. The results of the study can be useful for laser processing of materials, surface treatment by low-energy plasma, and also in radiation materials science.

The characteristics of quasi-breathers in monatomic fcc metals are investigated by the molecular dynamics method. The standard deviations of the frequencies of atoms constituting a breather from the fundamental frequency of oscillations are calculated. It is shown that the quasi-breather lifetime in the models under investigation depends on the initial excitation conditions as well as on the metal type.

The research of quasi-breather statistical characteristics in the model crystal of A3B stoichiometry is conducted by means of molecular dynamics method in the paper by the example of Pt3Al. The phonon spectrum of this model crystal, the dependences of mean-square deviation, the coefficient of variation and the average frequency of the model quasi-breather on the time of its existence are obtained. The statistical data analysis allows for the conclusion that a quasi-breather model solution slightly differs from the exact breather corresponding to it in the model under consideration using the interatomic potential obtained by means of embedded atom method (EAM).

Recent nuclear magnetic resonance studies [A. Pustogow et al., Nature 574, 72 (2019)] have challenged the prevalent chiral triplet pairing scenario proposed for Sr_{2}RuO_{4}. To provide guidance from microscopic theory as to which other pair states might be compatible with the new data, we perform a detailed theoretical study of spin fluctuation mediated pairing for this compound. We map out the phase diagram as a function of spin-orbit coupling, interaction parameters, and band structure properties over physically reasonable ranges, comparing when possible with photoemission and inelastic neutron scattering data information. We find that even-parity pseudospin singlet solutions dominate large regions of the phase diagram, but in certain regimes spin-orbit coupling favors a near-nodal odd-parity triplet superconducting state, which is either helical or chiral depending on the proximity of the γ band to the van Hove points. A surprising near degeneracy of the nodal s^{'} and d_{x^{2}-y^{2}} wave solutions leads to the possibility of a near-nodal time-reversal symmetry broken s^{'}+id_{x^{2}-y^{2}} pair state. Predictions for the temperature dependence of the Knight shift for fields in and out of plane are presented for all states.

The article deals with the preparation of animated content for mixed reality systems in solid state physics. The main obstacle to the mass adoption of these technologies is the complexity of model development. Here we have proposed one of the possible ways to simplify the creation of three-dimensional models for a course in solid state physics. In turn, the volumetric model can be supplemented with animated effects, which will provide greater interactivity and information content of the processes and phenomena under consideration. The proposed scheme is used to create models for the preparation of future physics teachers both in the process of teaching physics and directly for developing models. A survey was conducted among students about the complexity of developing such models. The results obtained testify in favor of the use of such methods both in teaching physics itself and in forming a base of models.

The introduction of modern technologies in the learning process at school is an important task, both for the education system as a whole and for an individual teacher. The ability to work with new teaching aids allows the teacher to interest students in their subject. One of these tools is virtual and mixed reality headsets. The emphasis is on mixed reality, although the two are often closely related. The article provides a brief overview of works devoted to the use of mixed reality in teaching physics, a study of the readiness of students of a pedagogical university to use this technology in their future professional activities is carried out. The questionnaire for expert assessment of mixed reality developments has been modified, and a survey of experts in this field has been conducted. The results of the research may be of interest to teachers of various specialties, senior students and graduate students in the field of physics teaching methods.

The article uses the molecular-dynamic method to calculate the statistical characteristics of a quasi-breather in a CuPt7 model crystal. In the calculations, a high-performance computing complex based on a GPU accelerator was used, which provided the necessary speed and accuracy of calculations. The phonon spectrum of this model crystal was calculated, and the dependences of the standard deviation, coefficient of variation, and average frequency of the model quasi-breather on its lifetime were revealed. The analysis of statistical data allows concluding that in the model under consideration, using the interatomic interaction potential obtained by the immersed atom (EAM) method, the quasi-breather model solution does not differ significantly from the corresponding exact breather. Moreover, the final destruction of the quasi-breather occurs at a time when the standard deviation of the frequencies exceeds the difference between the average frequency of the quasi-breather and the upper boundary of the phonon spectrum of the crystal. At this moment, the delocalization of vibrations and the dissipation of energy through the crystal in the form of low-amplitude thermal vibrations of the lattice occur. This may indicate the stability of the obtained discrete breather and the possibility of excitation in real alloys of the considered composition.

In this article, we study the structure of the network of dislocations near the boundary of a dicotyledonous bimetal Ni-Al under intense external harmonic influence. The method of molecular dynamics was chosen as the method, using potentials obtained by the immersed atom method. The paper analyzes the behavior of dislocation segments as a function of the intensity of exposure in the presence of vacancies near the boundary of a bipartite bimetal. It is shown that the frequency of exposure significantly affects the change in the structure of bimetal. In this case, point defects in the form of vacancies play an important role. The analysis was carried out by heating the calculated cells, the temperature of which is not more than half the melting temperature of the materials. Comparison with annealing of defects showed that structural changes in dislocations occur at lower temperatures, and their flow rate is higher.

The discrete breathers in a Pt3Al crystal, which exhibit soft (DB1) and hard (DB2) nonlinearity, are shown to possess a number of principal differences. Unlike an immobile and stable DB1, a DB2 breather is mainly localized on four Al atoms and is stretched along one of the close-packed rows of crystals. On the other hand, DB2 can displace hundreds of nanometers along one of the directions of close packing. Having localized a considerable amount of energy, both DB1 and DB2 breathers slowly emit it during their lifetime. A collision of DB1 and DB2 results in part of their energy being released into the Al sublattice, the larger part lost by DB2 that is destroyed faster than DB1. The DB2 breather can effectively transport the energy throughout the crystal, and a collision of DBs results in its considerable localization in the crystal. A capability of transferring the energy can thus give rise to structural transformations far from the focus of excitation of such localized objects.

By method of molecular dynamics investigated the interaction of nonlinear localized modes with bivacancies Pt crystal Pt3Al. Identified dependences of the lifetime of the nonlinear localized modes from the initial temperature of the crystal model, the initial atom Al deviation from its equilibrium position, as well as the distance to the introduced bivacancy Pt in (111) plane of the crystal.

It is known that, in a molecular dynamics model of Pt3Al crystal, a discrete breather (DB) with soft type nonlinearity (DB1) can be excited, which is characterized by a high degree of localization on a light atom (Al), stationarity, as well as a frequency that lies in the gap of the phonon spectrum and decreases with increasing amplitude of the DB. In this paper, it is demonstrated that a DB with hard type nonlinearity (DB2) can be excited in a Pt3Al nanofiber; this DB is localized on several light atoms, can move along the crystal, and has a frequency that lies above the phonon spectrum and increases with the DB amplitude. It is noteworthy that the presence of free surfaces of a nanofiber does not prevent the existence of DB1 and DB2 in it. Collisions of two DBs counterpropagating with equal velocities, as well as a collision of DB2 with a standing DB1, are considered. Two colliding DBs with hard type nonlinearity are repelled almost elastically, losing only insignificant part of their energy during the interaction. DB2 is also reflected from a standing DB1; in this case, the energy of the breathers is partially scattered into the Al sublattice. The results obtained indicate that DBs can transfer energy along a crystal over large distances. During the collision of two or more DBs, the energy localized in space can be as high as a few electron-volts; this allows one to raise the question of the participation of DBs in structural transformations of the crystal.

Molecular dynamics is used in this work to study the energy transport through the CuAu crystal lattice by discrete breathers (DBs) with frequencies above the phonon spectrum. The DB moves along the close packed atomic row in the Cu sublattice. An asymmetry was introduced in the initial conditions used for DB excitation in order to set the DB in motion. The maximal distance travelled by the DB was calculated as the function of the asymmetry parameter. The results indicate a weak mobility of such objects in the considered CuAu crystal. Nevertheless, energy transport along the close-packed directions of the Cu sublattice is possible.

Background The tumour microenvironment consists of malignant cells, stroma and immune cells. In women with large and locally advanced breast cancers (LLABCs) undergoing neoadjuvant chemotherapy (NAC), tumour-infiltrating lymphocytes (TILs), various subsets (effector, regulatory) and cytokines in the primary tumour play a key role in the induction of tumour cell death and a pathological complete response (pCR) with NAC. Their contribution to a pCR in nodal metastases, however, is poorly studied and was investigated. Methods Axillary lymph nodes (ALNs) (24 with and 9 without metastases) from women with LLABCs undergoing NAC were immunohistochemically assessed for TILs, T effector and regulatory cell subsets, NK cells and cytokine expression using labelled antibodies, employing established semi-quantitative methods. IBM SPSS statistical package (21v) was used. Non-parametric (paired and unpaired) statistical analyses were performed. Univariate and multivariate regression analyses were carried out to establish the prediction of a pCR and Spearman’s Correlation Coefficient was used to determine the correlation of immune cell infiltrates in ALN metastatic and primary breast tumours. Results In ALN metastases high levels of TILs, CD4+ and CD8+ T and CD56+ NK cells were significantly associated with pCRs.. Significantly higher levels of Tregs (FOXP3+, CTLA-4+) and CD56+ NK cells were documented in ALN metastases than in the corresponding primary breast tumours. CD8+ T and CD56+ NK cells showed a positive correlation between metastatic and primary tumours. A high % CD8+ and low % FOXP3+ T cells and high CD8+: FOXP3+ ratio in metastatic ALNs (tumour-free para-cortex) were associated with pCRs. Metastatic ALNs expressed high IL-10, low IL-2 and IFN-ϒ. Conclusions Our study has provided new data characterising the possible contribution of T effector and regulatory cells and NK cells and T helper1 and 2 cytokines to tumour cell death associated with NAC in ALNs. Trial registration The Trial was retrospectively registered. Study Registration Number is ISRCTN00407556. Electronic supplementary material The online version of this article (10.1186/s12885-018-4044-z) contains supplementary material, which is available to authorized users.

Energy localization in the ordered condensed systems is analyzed using А3В alloys with L12 superstructure. Using molecular dynamics, possible localization of phonon vibration energy in the aluminum sublattice and generation of a localized mode oscillating at a frequency belonging to the phonon spectrum energy gap and not representing a breather is considered for the ordered Pt3Al and Ni3Al alloys with L12 superstructure, which possess translational symmetry. Manifestations of anharmonicity in the atomic interactions and the relevant features of energy redistribution between sublattices of the ordered alloys are investigated. It is found out that in the ordered alloys of an A3B stoichiometry with L12 superstructure, whose phonon spectrum has a forbidden energy gap, vibrational energy can localize on the sublattice of B atoms. The alloys, found in a state of thermodynamic equilibrium at a certain temperature, are characterized by a local effect of spontaneous energy localization (the effect of energy redistribution between the lattices).

This article analyzes the structure and properties of the CuPt7 crystal for the possible existence of non-linear high-amplitude oscillations of the light alloy component. The densities of the phonon states of a crystal are calculated and analyzed for its different structures. It is demonstrated that the phonon system of a crystal has a narrow forbidden zone. The dependences of the possibility of the existence of high-amplitude oscillations on the initial conditions are revealed. It is shown that such oscillations are possible with the initial deviation of the Cu atom from the equilibrium position by more than 0.95 Å for FCC CuPt7. For such oscillators, their lifetime, the amount of stored energy, and other characteristics were obtained, which make it possible to characterize nonlinear high-amplitude lattice vibrations.

In this article, using the first-principle approach and the method of molecular dynamics, the authors investigate the properties of a Pt3Al crystal with a view to the possibility of the existence of such waves of soliton-like waves as discrete breathers. Methodical aspects of crystal models building are presented, with the analysis of the advantages and disadvantages of each method. Such crystal properties as the density distribution of phonon states, dispersion curves, and electron density distribution are studied. Based on the density functional theory, it is shown that the spectrum of the crystal does not have a through band gap, however, along the directions, it is possible to excite high-amplitude long-lived modes on Al atoms. The results indicate the benefit of the concept of discrete breathers in the investigated crystal.

The molecular dynamics method is used to consider the effect of energy transport in an A3B stoichiometry crystal, using Pt3Al as an example, which consists in the transfer of energy at frequencies outside the phonon spectrum of the crystal. This effect is called the effect of nonlinear supratransmission. The model was a bulk face-centered cubic crystal, the atoms of which interacted through a multi-particle potential, obtained by the immersed atom method. Different forms of oscillation of the region of external influence are considered. The possibility of transporting energy from the crystal surface into the depths by means of excitation of quasi-breathers near the impact area and their subsequent destruction in a crystal and dissipation of energy, stored on them, is shown. The quasi-breathers most intensely occurred near the impact region with a sinusoidal waveform. The results obtained indicate that the contribution of quasi-breathers to the energy transfer through the crystal, increases with increasing exposure amplitude. The minimum amplitude of the external influence, at which this effect was observed, is established. The results of the study can be useful in creating materials with predetermined properties, through various intensive external influences.