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Phonon maser stimulated by spin post-selectionFeb 08 2019In a sequence of single spins interacting dispersively with a mechanical oscillator, and using the micromaser model with random injection, we show that after an appropriate post-selection of each spin, a phonon laser analog with Poisson statistics is ... More

Specificity of Phase Transition of Quasi-Spin System in Two-Quantum Exchange with ThermostatJul 07 2008The quantum phase transition of the system of N radiators in case of two-photon exchange interaction with cavity electromagnetic field is considered. It is shown that for this system the atom-field exchange integral increases with the increase of temperature. ... More

Cooperative Two-Quantum Interaction of Excited System with BathJun 24 2004The problem of the two-photon coherent generation of entanglement photon pairs in Quantum Optics has been intensively studied for the last years. It is important to note that the two-quantum cooperative effects play a main role in other fields of physics ... More

Selftrapping triggered by losses in cavity QEDDec 23 2014In a coupled cavity QED network model, we study the transition from a localized super fluid like state to a delocalized Mott insulator like state, triggered by losses. Without cavity losses, the transition never takes place. Further, if one measures the ... More

Ground-state cooling of a nanomechanical oscillator with N spinsJul 30 2018Oct 26 2018Typical of modern quantum technologies employing nanomechanical oscillators is to demand few mechanical quantum excitations, for instance, to prolong coherence times of a particular task or, to engineer a specific non-classical state. For this reason, ... More

The power of a control qubit in weak measurementsSep 28 2016In the late 80s, a curious effect suggested by Aharanov, Albert and Vaidman opened up new vistas regarding quantum measurements on weakly coupled systems. There, a combination of a "weak" finite interaction together with a "strong" post-selection measurement ... More

Macroscopic non-classical state preparation via post-selectionDec 09 2016Dec 04 2017Macroscopic mechanical qubits are fundamental both to test the classical-quantum boundary and present suitable candidates for quantum information processing. Motivated by these, we propose a feasible probabilistic scheme to generate an on-demand mechanical ... More

Thermally generated long-lived quantum correlations for two atoms trapped in fiber-coupled cavitiesNov 22 2011Apr 25 2012A theoretical model for driving a two qubit system to a stable long-lived entanglement is discussed. The entire system is represented by two atoms, initially in ground states and disentangled, each one coupled to a separate cavity with the cavities connected ... More

The size impact on evolutionary dynamics of agents-clusterApr 25 2003A cluster theory based mathematical model was developed and used to simulate the dynamics of a system composed of a large number of interacting agents-clusters with different size. The case of a system formed by a constant total number of economic units ... More

Thermal effects on the sudden changes and freezing of correlations between remote atoms in cavity QED networkFeb 10 2014We investigate the thermal effects on the sudden changes and freezing of the quantum and classical correlations of remote qubits in a cavity quantum electrodynamics (CQED) network with losses. We find that the detrimental effect of the thermal reservoirs ... More

Generation and protection of Maximally Entangled State between many modes in an optical network with dissipationOct 03 2016We present a three-cavity network model with two modes in each cavity and a non-linear medium that generates a Kerr type interaction via both self-phase and cross-phase modulation processes. We have two main goals. The first one is to generate a multipartite ... More

Quantum Correlations in Cavity QED NetworksJul 21 2014We present a Review of the dynamical features such as generation, propagation, distribution, sudden transition and freezing of the various quantum correlation measures, as Concurrence, Entanglement of Formation, Quantum Discord, as well their geometrical ... More

Hitting times of local and global optima in genetic algorithms with very high selection pressureJun 18 2016Jun 30 2016The paper is devoted to upper bounds on the expected first hitting times of the sets of local or global optima for non-elitist genetic algorithms with very high selection pressure. The results of this paper extend the range of situations where the upper ... More

Non-Elitist Genetic Algorithm as a Local Search MethodJul 12 2013Mar 28 2014Sufficient conditions are found under which the iterated non-elitist genetic algorithm with tournament selection first visits a local optimum in polynomially bounded time on average. It is shown that these conditions are satisfied on a class of problems ... More

On Proportions of Fit Individuals in Population of Evolutionary Algorithm with Tournament SelectionJul 29 2015Aug 26 2016In this paper, we consider a fitness-level model of a non-elitist mutation-only evolutionary algorithm (EA) with tournament selection. The model provides upper and lower bounds for the expected proportion of the individuals with fitness above given thresholds. ... More

On complexity of optimized crossover for binary representationsMay 25 2007We consider the computational complexity of producing the best possible offspring in a crossover, given two solutions of the parents. The crossover operators are studied on the class of Boolean linear programming problems, where the Boolean vector of ... More

Evolutionary algorithmsNov 22 2015This manuscript contains an outline of lectures course "Evolutionary Algorithms" read by the author in Omsk State University n.a. F.M.Dostoevsky. The course covers Canonic Genetic Algorithm and various other genetic algorithms as well as evolutioanry ... More

Modularity in biological evolution and evolutionary computationNov 19 2018One of the main properties of biological systems is modularity, which manifests itself at all levels of their organization, starting with the level of molecular genetics, ending with the level of whole organisms and their communities. In a simplified ... More

On Solving Travelling Salesman Problem with Vertex RequisitionsMar 11 2017We consider the Travelling Salesman Problem with Vertex Requisitions, where for each position of the tour at most two possible vertices are given. It is known that the problem is strongly NP-hard. The proposed algorithm for this problem has less time ... More

Towards a random laser with cold atomsJun 03 2009Jul 22 2009Atoms can scatter light and they can also amplify it by stimulated emission. From this simple starting point, we examine the possibility of realizing a random laser in a cloud of laser-cooled atoms. The answer is not obvious as both processes (elastic ... More

Characterization of superconducting RF breakdown by two-mode excitationOct 25 2013We show that thermal and magnetic contributions to the breakdown of superconductivity in radiofrequency (RF) fields can be separated by applying two RF modes simultaneously to a superconducting surface. We develop a simple model that illustrates how mode-mixing ... More

Analysis of Optimal Recombination in Genetic Algorithm for a Scheduling Problem with SetupsDec 16 2014In this paper, we perform an experimental study of optimal recombination operator for makespan minimization problem on single machine with sequence-dependent setup times ($1|s_{vu}|C_{\max}$). The computational experiment on benchmark problems from TSPLIB ... More

Genetic Algorithm with Optimal Recombination for the Asymmetric Travelling Salesman ProblemJun 21 2017Dec 19 2017We propose a new genetic algorithm with optimal recombination for the asymmetric instances of travelling salesman problem. The algorithm incorporates several new features that contribute to its effectiveness: (i) Optimal recombination problem is solved ... More

Optimal Recombination in Genetic AlgorithmsJul 21 2013This paper surveys results on complexity of the optimal recombination problem (ORP), which consists in finding the best possible offspring as a result of a recombination operator in a genetic algorithm, given two parent solutions. We consider efficient ... More

Evolutionary Algorithms and Dynamic ProgrammingJan 17 2013Recently, it has been proven that evolutionary algorithms produce good results for a wide range of combinatorial optimization problems. Some of the considered problems are tackled by evolutionary algorithms that use a representation which enables them ... More

Level-Based Analysis of Genetic Algorithms for Combinatorial OptimizationDec 07 2015Dec 09 2015The paper is devoted to upper bounds on run-time of Non-Elitist Genetic Algorithms until some target subset of solutions is visited for the first time. In particular, we consider the sets of optimal solutions and the sets of local optima as the target ... More

Locally Anisotropic Wormholes and Flux Tubes in 5D GravityMar 15 2001Aug 29 2001In this article we examine a class of wormhole and flux tube like solutions to 5D vacuum Einstein equations. These solutions possess generic local anisotropy, and their local isotropic limit is shown to be conformally equivalent to the spherically symmetric ... More

Reducing the Number of Changeover Constraints in a MIP Formulation of a Continuous-Time Scheduling ProblemAug 25 2014In this paper, we develop a new formulation of changeover constraints for mixed integer programming problem (MIP) that emerges in solving a short-term production scheduling problem. The new model requires fewer constraints than the original formulation ... More

Protection of Information from Imitation on the Basis of Crypt-Code StructuresSep 07 2018A system is offered for imitation resistant transmitting of encrypted information in wireless communication networks on the basis of redundant residue polynomial codes. The particular feature of this solution is complexing of methods for cryptographic ... More

Glass Transition in Confined GeometryAug 23 2010Extending mode-coupling theory, we elaborate a microscopic theory for the glass transition of liquids confined between two parallel flat hard walls. The theory contains the standard MCT equations in bulk and in two dimensions as limiting cases and requires ... More

Approximate solution of length-bounded maximum multicommodity flow with unit edge-lengthsAug 02 2017An improved fully polynomial-time approximation scheme and a greedy heuristic for the fractional length-bounded maximum multicommodity flow problem with unit edge-lengths are proposed. Computational experiments are carried out on benchmark graphs and ... More

Magnetic proximity effect in the 3D topological insulator/ferromagnetic insulator heterostructureMay 07 2013We theoretically study the magnetic proximity effect in the three dimensional (3D) topological insulator/ferromagnetic insulator (TI/FMI) structures in the context of possibility to manage the Dirac helical state in TI. Within continual approach based ... More

Ideal two-dimensional electron systems with a giant Rashba-type spin splitting in real materials: surfaces of bismuth tellurohalidesMay 09 2012Spintronics is aimed at active controlling and manipulating the spin degrees of freedom in semiconductor devices. A promising way to achieve this goal is to make use of the tunable Rashba effect that relies on the spin-orbit interaction (SOI) in a two-dimensional ... More

Magnetic proximity effect at the 3D topological insulator/magnetic insulator interfaceApr 04 2013The magnetic proximity effect is a fundamental feature of heterostructures composed of layers of topological insulators and magnetic materials since it underlies many potential applications in devices with novel quantum functionality. Within density functional ... More

New interpretation of the origin of 2DEG states at the surface of layered topological insulatorsJul 16 2011On the basis of relativistic ab-initio calculations we show that the driving mechanism of simultaneous emergence of parabolic and M-shaped 2D electron gas (2DEG) bands at the surface of layered topological insulators as well as Rashba-splitting of the ... More

Many-body effects on the Rashba-type spin splitting in bulk bismuth tellurohalidesMar 20 2013Apr 25 2013We report on many-body corrections to one-electron energy spectra of bulk bismuth tellurohalides---materials that exhibit a giant Rashba-type spin splitting of the band-gap edge states. We show that the corrections obtained in the one-shot $GW$ approximation ... More

New topological surface state in layered topological insulators: unoccupied Dirac coneMar 11 2013The unoccupied states in topological insulators Bi_2Se_3, PbSb_2Te_4, and Pb_2Bi_2Te_2S_3 are studied by the density functional theory methods. It is shown that a surface state with linear dispersion emerges in the inverted conduction band energy gap ... More

Topologically nontrivial centrosymmetric thin films constructed from BiTeI trilayers: ab initio calculations and model HamiltoniansJul 22 2016Based on ab initio calculations, we show that quantum spin Hall insulator (QSHI) phase can be realized in the ultra thin films constructed from a trivial band insulator with strong spin-orbit coupling. The thinnest QSHI with an inverted gap wide enough ... More

Spin-helical Dirac states in graphene induced by polar-substrate surfaces with giant spin-orbit interaction: a new platform for spintronicsJun 18 2014Spintronics, or spin electronics, is aimed at efficient control and manipulation of spin degrees of freedom in electron systems. To comply with demands of nowaday spintronics, the studies of electron systems hosting giant spin-orbit-split electron states ... More

Rashba split surface states in BiTeBrFeb 04 2013Within density functional theory, we study bulk band structure and surface states of BiTeBr. We consider both ordered and disordered phases which differ in atomic order in the Te-Br sublattice. On the basis of relativistic ab-initio calculations, we show ... More

Interface induced states at the boundary between a 3D topological insulator Bi$_2$Se$_3$ and a ferromagnetic insulator EuSJul 25 2014By means of relativistic density functional theory (DFT) calculations we study electron band structure of the topological insulator (TI) Bi$_2$Se$_3$ thin films deposited on the ferromagnetic insulator (FMI) EuS substrate. In the Bi$_2$Se$_3$/EuS heterostructure, ... More

On Finding Maximum Cardinality Subset of Vectors with a Constraint on Normalized Squared Length of Vectors SumJul 19 2017In this paper, we consider the problem of finding a maximum cardinality subset of vectors, given a constraint on the normalized squared length of vectors sum. This problem is closely related to Problem 1 from (Eremeev, Kel'manov, Pyatkin, 2016). The main ... More

Level-based Analysis of Genetic Algorithms and other Search ProcessesJul 29 2014Oct 27 2016Understanding how the time-complexity of evolutionary algorithms (EAs) depend on their parameter settings and characteristics of fitness landscapes is a fundamental problem in evolutionary computation. Most rigorous results were derived using a handful ... More

Modeling Near-Surface Bound Electron States in Three-Dimensional Topological Insulator: Analytical and Numerical ApproachesJun 27 2014We apply both analytical and ab-initio methods to explore heterostructures composed of a threedimensional topological insulator (3D TI) and an ultrathin normal insulator (NI) overlayer as a proof ground for the principles of the topological phase engineering. ... More

Non-Dirac topological surface states in (SnTe)$_{n\geq2}$(Bi$_2$Te$_3$)$_{m=1}$May 28 2015A new type of topological spin-helical surface states was discovered in layered van der Waals bonded (SnTe)$_{n=2,3}$(Bi$_2$Te$_3$)$_{m=1}$ compounds which comprise two covalently bonded band inverted subsystems, SnTe and Bi$_2$Te$_3$, within a building ... More

Quantum theory of a two-mode open-cavity laserMay 09 2011Aug 25 2011We develop the quantum theory of an open-cavity laser assuming that only two modes compete for gain. We show that the modes interact to build up a collective mode that becomes the lasing mode when pumping exceeds a threshold. This collective mode exhibits ... More

Unique thickness-dependent properties of the van der Waals interlayer antiferromagnet $\mathrm{MnBi_2Te_4}$ filmsOct 11 2018Using density functional theory and Monte Carlo calculations, we study the thickness dependence of the magnetic and electronic properties of a van der Waals interlayer antiferromagnet in the two-dimensional limit. Considering $\mathrm{MnBi_2Te_4}$ as ... More

Termination-dependent surface properties in the giant-Rashba semiconductors BiTeX (X = Cl, Br, I)Nov 20 2015The non-centrosymmetric semiconductors BiTeX (X = Cl, Br, I) show large Rashba-type spin-orbit splittings in their electronic structure making them candidate materials for spin-based electronics. However, BiTeI(0001) single crystal surfaces usually consist ... More

Topological Surface States with Persistent High Spin Polarization across Dirac Point in Bi$_{2}$Te$_{2}$Se and Bi$_{2}$Se$_{2}$TeMar 20 2012Helical spin textures with the marked spin polarizations of topological surface states have been firstly unveiled by the state-of-the-art spin- and angle-resolved photoemission spectroscopy for two promising topological insulators Bi$_2$Te$_2$Se and Bi$_2$Se$_2$Te. ... More

Quasiparticle interference on the surface of 3D topological insulator Bi$_{2}$Se$_{3}$ induced by cobalt adatom in the absence of ferromagnetic orderingDec 14 2011Dec 15 2011Quasiparticle interference induced by cobalt adatoms on the surface of the topological insulator Bi$_{2}$Se$_{3}$ is studied by scanning tunneling microscopy, angle-resolved photoemission spectroscopy and X-ray magnetic circular dichroism. It is found ... More

Experimental verification of PbBi$_{2}$Te$_{4}$ as a 3D topological insulatorNov 24 2011Mar 05 2012The first experimental evidence is presented of the topological insulator state in PbBi$_{2}$Te$_{4}$. A single surface Dirac cone is observed by angle-resolved photoemission spectroscopy (ARPES) with synchrotron radiation. Topological invariants $\mathbb{Z}_2$ ... More

Unoccupied Topological States on Bismuth ChalcogenidesOct 11 2012Oct 16 2012The unoccupied part of the band structure of topological insulators Bi$_2$Te$_{x}$Se$_{3-x}$ ($x=0,2,3$) is studied by angle-resolved two-photon photoemission and density functional theory. For all surfaces linearly-dispersing surface states are found ... More

Surface and bulk Fermiology and band dispersion in non-centrosymmetric BiTeIApr 10 2012BiTeI has a layered and non-centrosymmetric structure where strong spin-orbit interaction leads to a giant spin splitting in the bulk bands. Here we present high-resolution angle-resolved photoemission (ARPES) data in the UV and soft x-ray regime that ... More

Real-time Observation of Phonon-Mediated $σ$-$π$ Interband Scattering in MgB2Jan 17 2017In systems having an anisotropic electronic structure, such as the layered materials graphite, graphene and cuprates, impulsive light excitation can coherently stimulate specific bosonic modes, with exotic consequences for the emergent electronic properties. ... More

Large-gap magnetic topological heterostructure formed by subsurface incorporation of a ferromagnetic layerSep 06 2017Inducing magnetism into topological insulators is intriguing for utilizing exotic phenomena such as the quantum anomalous Hall effect (QAHE) for technological applications. While most studies have focused on doping magnetic impurities to open a gap at ... More

Relocation of the topological surface state of Bi$_{2}$Se$_{3}$ beneath the surface by Ag intercalationDec 26 2011We studied the Ag-intercalated 3D topological insulator Bi$_{2}$Se$_{3}$ by scanning tunneling microscopy/spectroscopy and angle-resolved photoemission spectroscopy, combined with a first principles calculations. We demonstrate that silver atoms deposited ... More

First results from the TUS orbital detector in the extensive air shower modeApr 25 2017Sep 26 2017TUS (Tracking Ultraviolet Set-up), the first orbital detector of extreme energy cosmic rays (EECRs), those with energies above 50 EeV, was launched into orbit on April 28, 2016, as a part of the Lomonosov satellite scientific payload. The main aim of ... More

Search for extreme energy cosmic ray candidates in the TUS orbital experiment dataJun 16 2017TUS (Track Ultraviolet Setup) is the first space experiment aimed to check the possibility of registering extreme energy cosmic rays (EECRs) at E>50 EeV by measuring the fluorescence signal of extensive air showers in the atmosphere. The detector operates ... More

Prediction and observation of the first antiferromagnetic topological insulatorSep 19 2018Despite immense advances in the field of topological materials, the antiferromagnetic topological insulator (AFMTI) state, predicted in 2010, has been resisting experimental observation up to now. Here, using density functional theory and Monte Carlo ... More

First results of the Lomonosov TUS and GRB experimentsMar 10 2017Mar 26 2017On April 28, 2016, the Lomonosov satellite, equipped with a number of scientific instruments, was launched into orbit. Here we present briefly some of the results obtained with the first orbital telescope of extreme energy cosmic rays TUS and by a group ... More