One of the primary tasks of ensuring the safety of objects in contact with polluting objects (for example, radiation waste) is to assess the risks associated with the possible spread of impurities over long distances. Experiments that were carried out on a real natural scale, in which the migration of an impurity injected into a layer including a network of migration channels was studied under...
There are well-defined indications, following from experimental studies of compressibility (adiabatic compressibility is measured using sound speed measurements, and then isothermal compressibility is restored), to the existence of a dependence of the compressibility of simple bi-component mixtures not only on the molar fractions of the components [1]. It can be assumed that this parameter may...
For many years the question of finite-size scaling above the upper critical dimension dc was a source of many new theoretical results as well as new and interesting works in computer simulations, see [1] for a review . While in the thermodynamic limit system’s scaling behaviour is mean-field, for the finitesize systems two scaling regimes are being considered. Simple approach is a trivial...
The research is dedicated to a detailed theoretical study of dynamic processes that occur during the interaction of a transmon-type qubit connected to a semi-infinite transmission line with two signals: pump and probe. By manipulating the frequencies and amplitudes of the signals it is possible to explore the system behavior. We use the Lindblad equation formalism to make our calculations....
Quantum logic gates applied to qubits are basic elements of the circuit model used for quantum computations. Usually, quantum gates are realized by a resonant excitation, resulting in Rabi oscillations, which lead to a periodic excitation of the qubit. It has certain limitations and complications, like neglecting counter-rotating terms. We investigate an alternative way for quantum control and...
We investigated the electronic processes in a field effect transistor channel using shallow water approximations to obtain the analytical expressions for electron and field distributions, as well as electric fluctuations using the Langevin approach. We considered the current-voltage characteristic of the transistor in the stationary mode. For the non-stationary case, we obtained the spatial...
Motivated by recent experimental observations of unconventional superconductivity in the twisted bilayer and trilayer graphene, we develop a theory of point-contact tunneling into superconductors with arbitrary gap structures and for arbitrary transmission coefficients of the contact. Exploiting the dependence of Andreev reflections on the position of the STM tip relative to lattice symmetry...
We elaborate a systematic way to obtain higher order contributions in the nonlinear steepest descent method for Riemann-Hilbert problem associated with homogeneous Painleve II equation. The problem is reformulated as a matrix factorization problem on two circles and can be solved perturbatively reducing it to finite systems of algebraic linear equations. The method is applied to find...
In our work we consider geodesic equations in Schwarzschild space-time with arbitrary external forces and obtain Gaussian perturbation equations for osculating elements in terms of Weierstrass elliptic functions. As an application, we solve the perturbation equations analytically in linear approximation for forces induced by the presence of the cosmological constant in the Schwarzschild-de...
The change in conformation during biological functioning is a characteristic feature of biomolecules. The presence of various conformers complicates their physics-based modeling, as the properties of each conformer need to be determined separately. Moreover, the relative energies of the conformers become an additional quantity of interest because they determine the probability of each...
In this paper, a computer simulation of radiation-induced segregation in the Fe-20Cr-8Ni alloy was carried out within the framework of the modified inverse Kirkendall model [1-3]. The dependences of the concentrations of Cr and Ni atoms on the surface of the sample on the rate of production of point defects and temperature, as well as the concentration profiles of Cr and Ni atoms and point...
Significant successes and important results of research on synchrotron radiation sources raised a new urgent question, namely the development of bright compact radiation sources with coherence parameters that allow the implementation of phase-informative methods. This is due to the growing demand for the use of new research methods based on X-ray radiation in engineering, materials science and...
Curvilinear magnetism is an emerging field which connects low-dimensional magnetic architectures with their geometrical properties to describe resulting novel phenomena. Nanoscale curved magnetic stripes are a crucial building block in the race for high-density and ultrafast magnetic memory, and can substantially augment the performance of spintronic devices [1,2].
Here, we aim to...
The resonating group method (RGM) [1] is a rigorous and self-consistent realization of cluster model. It has been numerously proved the RGM is a powerful tool to study the structure of light atomic nuclei and nuclear reactions of different types. Thus it equally well describes bound and continuous spectrum states. The main advantages of the RGM is that it takes into account the internal...
We will present the results of a study of the bremsstrahlung emission of photons in a process of proton scattering on deuterons. Despite the long history of studies of the interaction of protons with deuterons and the existence of some studies on the subject in such reactions there are some interacting problems that need to be tackled. This stimulates us to develop a new model that allows us...
Collider experiments serve as an unique tool to create and study new forms of strongly interacting matter, such as quark-gluon plasma (QGP). This state of matter is believed to have existed in the microseconds after the Big Bang when temperatures and energy densities were extremely high. However, due to confinement under typical Earth conditions, elementary particles of quantum chromodynamics...
As a part of the ATLAS Collaboration experimental measurements of light-by-light
scattering in Pb+Pb collisions during 2015 and 2018 at an integrated luminosity of 2.2 nb-1 and energy of 5.02 TeV, taking into account the obtained experimental constraints [1], we have modeled the production cross sections of axion production, which is candidate for dark matter with subsequent decay into γγ....
There exist many models of physics beyond the Standard model (SM) which introduce new heavy particles. Signals of such new states could be parametrized either within a complete model of new physics or its low-energy approximation. The latter consists of effective Lagrangian (EL), which describes effects of interactions with heavy particles on the dynamics of light fields when heavy states...
This work examines limitations on the neutrino extension parameters of the Standard Model of elementary particle physics. A simple relationship between the observed quantities, elements of the matrices S and R was obtained, which is valid for non-zero masses of active neutrinos and for different values of masses of heavy sterile neutrinos. Experimental constraints on the elements of the S and...
We extend the Quantum van der Waals description of isospin symmetric nuclear matter at zero temperature to a high baryon density region by incorporating the continuous transition to quark matter in accordance with the recently proposed quarkyonic approach. The resulting equation of state exhibits the nuclear liquid-gas transition at $n_B \leq \rho_0$ and undergoes a transition to quarkyonic...
We study the critical point effects on particle number fluctuations both in the crossover ($T > T_{\rm c}$) and mixed phase ($T < T_{\rm c}$) regions by means of molecular dynamics simulations of a Lennard-Jones fluid, motivated by the ongoing search for the QCD critical point in heavy-ion collisions.
In the crossover region, we find large fluctuations associated with the critical point in...
