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The effective field theory motivated relativistic mean-field (E-RMF) formalism is employed to study the equation of state (EoS) for the infinite symmetric nuclear matter (SNM) at finite temperature using the recently developed forces FSUGarnet, IOPB-I, G3, and the well known NL3 force parameter. The EoS is then used to estimate the critical temperature T c, pressure P c and density ρ c of the SNM for the liquid–gas phase transition. As T c is not a constrained parameter in both experiments and theoretical calculations, there is a large uncertainty around its value. Although, the critical parameters are correlated among themselves. It is revealed that vector self-coupling ζ 0 of used forces play determining role in EoS in finite temperature limit. Keeping the incompressibility in acceptable limit i.e. 240 ± 20 MeV, the lower value of ζ 0 gives a better result of T c when compared to the several experimental data. The critical parameters however show weak correlation with the properties at saturation density at zero temperature. The compressibility factors calculated with these parameters are in agreement with the universal value of liquid–gas systems. Stability conditions are examined along with binodal and spinodal regions. Besides this, the thermodynamic properties like specific heat and latent heat are also worked out. We have carried out detailed consistency check of our calculations using critical exponents and standard scaling laws. All the exponents are well within the theoretical mean-field results.

In this paper, we derive analytical time-dependent Green's functions in a two-dimensional, anisotropic elastic, and infinite solid. It is based on the Stroh formalism combined with application of the Cauchy's residue theorem. Final expressions of the Green's function are in terms of simple finite line integral from 0 to 2π. The time-dependence of the line forces can be impulsive, Heaviside, or within a given time duration. The space-dependence of the line force is very general, including concentrated or uniformly distributed sources within a given line interval. Green's functions of both displacements and stresses are derived in analytical forms, and are verified against existing results. Numerical examples are presented to demonstrate the effect of source types and material anisotropy on the Green's functions.

Connections between the Görling-Levy (GL) perturbation theory and the parameters of double-hybrid (DH) density functional are established via adiabatic connection formalism. Moreover, we present a more general DH density functional theory, where the higher-order perturbation terms beyond the second-order GL2 one, such as GL3 and GL4, also contribute. It is shown that a class of DH functionals including previously proposed ones can be formed using the present construction. Based on the proposed formalism, we assess the performance of higher-order DH and long-range corrected DH formed on the Perdew-Burke-Ernzerhof (PBE) semilocal functional and second-order GL2 correlation energy. The underlying construction of DH functionals based on the generalized many-body perturbation approaches is physically appealing in terms of the development of the non-local forms using more accurate and sophisticated semilocal functionals.

The equations of motion for the parametrized post-Newtonian (PPN) formalism for several S-stars close to the relativistic compact object Sgr A* at the center of the galaxy are examined. The effect of the difference in the periods of Newtonian and post-Newtonian orbits is taken into account. The period of the best approximation to the PN-orbit of the star S2 exceeds the period of the Newtonian orbit by 16 days. The PPN parameters βPPN and γPPN are measured. Bayesian methods are used for fitting the trajectories of the PPN motion. Posterior estimates of βPPN and γPPN $$ {0.97}_{-0.65}^{+0.42} $$ and $$ {0.81}_{-0.60}^{+0.46} $$ are obtained, respectively. This result confirms the prediction of the general theory of relativity for the post-Newtonian equations of motion under conditions close to Sgr A*.

Periodic photonic lattices constitute a fundamental pillar of physics supporting a plethora of scientific concepts and applications. The advent of metamaterials and metastructures is grounded in a ...

In this paper a general study of NV center internal state in diamond is presented. This study is based on experimental and theoretical findingsfound in literature. First, a Hamiltonian model for center NV internal state is proposed in terms of a complete set of commuting observables(CSCO), which consist of angular momentum ^L, spin momentum ^ S, total angular momentum ^ J = ^L+ ^ S and spin momentum on z-direction^ Sz. The second quantization formalism –in steady-state (conservative model)– is used. The creation and annihilation operators are used todescribed the steady spin-levels structure and in dynamic-state (non-conservative model) and can also describe the system dynamic betweendifferent spin-levels transitions. Finally, a discussion is presented about the application of this study in the photochromism phenomenon andsolid-state quantum bit (qubit).

Why proteins are fuzzy? Constant adaptation to the cellular environment requires a wide range of changes in protein structure and interactions. Conformational ensembles of disordered proteins in particular exhibit large shifts to activate or inhibit alternative pathways. Fuzziness is critical for liquid–liquid phase separation and conversion of biomolecular condensates into fibrils. Interpretation of these phenomena presents a challenge for the classical structure-function paradigm. Here I discuss a multi-valued formalism, based on fuzzy logic, which can be applied to describe complex cellular behavior of proteins.

Gravitational waves from supermassive black hole binary mergers along with an electromagnetic counterpart have the potential to shed ‘light’ on the nature of dark energy in the intermediate redshift regime. Accurate measurement of dark energy parameters at intermediate redshift is extremely essential to improve our understanding of dark energy, and to possibly resolve a couple of tensions involving cosmological parameters. We present a Fisher matrix forecast analysis in the context of eLISA to predict the errors for three different cases: the non-interacting dark energy with constant and evolving equation of state (EoS), and the interacting dark sectors with a generalized parametrization. In all three cases, we perform the analysis for two separate formalisms, namely, the standard EoS formalism and the Om parametrization which is a model-independent null diagnostic for a wide range of fiducial values in both phantom and non-phantom regions, to make a comparative analysis between the prospects of these two diagnostics in eLISA. Our analysis reveals that it is wiser and more effective to probe the null diagnostic instead of the standard EoS parameters for any possible signature of dark energy at intermediate redshift measurements like eLISA.

In this paper, we formulate the Mimetic theory of gravity in first-order formalism for differential forms, i.e., the mimetic version of Einstein-Cartan-Sciama-Kibble (ECSK) gravity. We consider different possibilities on how torsion is affected by Weyl transformations and discuss how this translates into the interpolation between two different Weyl transformations of the spin connection, parameterized with a zero-form parameter λ. We prove that regardless of the type of transformation one chooses, in this setting torsion remains as a non-propagating field. We also discuss the conservation of the mimetic stress-energy tensor and show that the trace of the total stress-energy tensor is not null but depends on both, the value of λ and spacetime torsion., P. M. is supported by Agencia Nacional de Investigaci´on (ANID) through the grant 21161574. OV acknowledges VRIIP UNAP for financial support through Project VRIIP0062-19 and Becas Chile grant 74200062. FI ad PS acknowledges financial support from the Chilean government through Fondecyt grant 1180681. NM, acknowledges Fondecyt grant 11180894.

The exact solutions of either spherical or deformed mean-field plus various types of pairing models are briefly reviewed. It is shown that, besides the standard pairing model, there are several special types of pairing interaction that can be solved exactly. In comparison to the standard pairing, the results of several pairing-driven quantities, such as pairing excitation energies, even–odd mass differences, the moment of inertia, etc., show that these types of pairing interaction can indeed be used to describe pairing correlations in nuclei either more accurately or efficiently. Moreover, the shape phase transitional behaviors of nuclei described by the consistent-Q formalism of the interacting boson model are summarized.

We consider radiation emitted by colour-charged and massive particles crossing strong plane wave backgrounds in gauge theory and gravity. These backgrounds are treated exactly and non-perturbatively throughout. We compute the back-reaction on these fields from the radiation emitted by the probe particles: classically through background-coupled worldline theories, and at tree-level in the quantum theory through three-point amplitudes. Consistency of these two methods is established explicitly. We show that the gauge theory and gravity amplitudes are related by the double copy for amplitudes on plane wave backgrounds. Finally, we demonstrate that in four-dimensions these calculations can be carried out with a background-dressed version of the massive spinor-helicity formalism., 34 pages, 1 figure. v2: published version, improvements to section 4.1

A new reactive force field based on the ReaxFF formalism is effectively parametrized against an extended training set of quantum chemistry data (containing more than 120 different structures) to describe accurately silver and silver-thiolate systems. The results obtained with this novel representation demonstrate that the novel ReaxFF paradigm is a powerful methodology to reproduce more appropriately average geometric and energetic properties of metal clusters and slabs when compared to the earlier ReaxFF parametrizations dealing with silver and gold. ReaxFF cannot describe adequately specific geometrical features such as the observed shorter distances between the under-coordinated atoms at the cluster edges. Geometric and energetic properties of thiolates adsorbed on a silver Ag20 pyramid are correctly represented by the new ReaxFF and compared with results for gold. The simulation of self-assembled monolayers of thiolates on a silver (111) surface does not indicate the formation of staples in contrast to the results for gold-thiolate systems.

In 2004, Dharam Vir Ahluwalia and Daniel Grumiller discovered a dark matter candidate called Elko: spin one-half fermions with mass dimension one. These fermions are described by a spinorial Klein-Gordon formalism and very different from electrons or neutrinos. In this review, we give a brief introduction to the localization of Elko spinor fields on branes. First, we briefly review some brane-world theories and the localization of bulk matter fields on branes. Then, after a brief introduction to Elko spinor fields, we focus on the localization of Elko fields on branes in three cases: the free Elko fields, the Elko fields with Yukawa-like coupling, and finally, the Elko fields with non-minimal coupling.

Let $T \in C^{2+ \varepsilon} (S^{1} \setminus \{x_{b} \})$, $\varepsilon> 0 $, be a circle homeomorphism with one break point $x_{b}$, at which $ T'(x) $ has a discontinuity of the first kind and both one-sided derivatives at the point $x_{b} $ are strictly positive. Assume that the rotation number $\rho_{T}$ is irrational and its decomposition into a continued fraction beginning from a certain place coincides with the golden mean, i.e., $\rho_{T}=[m_{1}, m_{2}, \ldots, m_{l}, \, m_{l + 1}, \ldots] $, $ m_{s} = 1$, $s> l> 0$. Since the rotation number is irrational, the map $ T $ is strictly ergodic, that is, possesses a unique probability invariant measure $\mu_{T}$. A.A. Dzhalilov and K.M. Khanin proved that the probability invariant measure $ \mu_{G} $ of any circle homeomorphism $ G \in C^{2+ \varepsilon} (S^{1} \setminus \{x_{b} \})$, $\varepsilon> 0$, with one break point $ x_{b} $ and the irrational rotation number $ \rho_{G} $ is singular with respect to the Lebesgue measure $ \lambda $ on the circle, i.e., there is a measurable subset of $ A \subset S^{1} $ such that $ \mu_ {G} (A) = 1 $ and $ \lambda (A) = 0$. We will construct a thermodynamic formalism for homeomorphisms $ T_{b} \in C^{2+ \varepsilon} (S^{1} \setminus \{x_{b} \})$, $\varepsilon> 0 $, with one break at the point $ x_{b} $ and rotation number equal to the golden mean, i.e., $ \rho_{T}:= \frac {\sqrt{5} -1}{2} $. Using the constructed thermodynamic formalism, we study the exponents of singularity of the invariant measure $ \mu_{T} $ of homeomorphism $ T $.

We discuss how the massive higher spin bosonic and fermionic fields in four-dimensional $$AdS$$ space can be described in the frame-like gauge invariant multispinor formalism. We consider both the Lagrangian formulation as well as the unfolded equations.

We review some fundamental aspects of mixed symmetry tensor gauge theories using a formulation based on graded geometry. In particular, we are able to construct kinetic, mass and Galileon-type higher derivative interaction terms for such fields. The resulting elegant geometric formulas allow for shared features of these theories to be highlighted and for possible interaction terms to be classified. In addition, we argue that this formalism is very useful in studying dualities. In particular, we construct a universal first order Lagrangian that may serve as the starting point for the off shell dualizations of differential form gauge theories and generalized gravitons.

International audience; This paper proposes a time-domain hybrid method for coupling Multiconductor-Transmission-Line Network equations and a Finite Element Method to evaluate the electromagnetic response of the electric wires of a cable-bundle located inside a 3 dimensional structure. The method is applied and demonstrated over a box structure made of several volumes containing a realistic multiconductor cable-harness and illuminated by a plane wave. The formalism of the method is given and the results obtained show the interest of this approach.; Ce papier propose une méthode d’hybridation temporelle pour coupler des équations de Réseaux de Lignes de Transmission Multiconducteurs et des équations d’une méthode aux éléments finis pour évaluer la réponse électromagnétique de câbles électriques de faisceaux de câbles installés dans une structure parfaitement métallique. La méthode est présentée et démontrées sur une structure de type boîte constituée de plusieurs volumes contenant un harnais de câbles réaliste et illuminée par une onde plane. Le formalisme de la méthode est donné et les résultats obtenus montrent l’intérêt de cette approche.

When considering a Li-intercalated hexagonal boron nitride bilayer (Li-hBN), the vertex corrections of electron–phonon interaction cannot be omitted. This is evidenced by the very high value of the ratio λωD/εF ≈ 0.46, where λ is the electron–phonon coupling constant, ωD is the Debye frequency, and εF represents the Fermi energy. Due to nonadiabatic effects, the phonon–induced superconducting state in Li-hBN is characterized by much lower values of the critical temperature (TLOVCC ∈ {19.1, 15.5, 11.8} K, for μ* ∈ {0.1, 0.14, 0.2}, respectively) than would result from calculations not taking this effect into account (TMEC∈ {31.9, 26.9, 21} K). From the technological point of view, the low value of TC limits the possible applications of Li-hBN. The calculations were carried out under the classic Migdal–Eliashberg formalism (ME) and the Eliashberg theory with lowest-order vertex corrections (LOVC). We show that the vertex corrections of higher order (λ3) lower the value of TLOVCC by a few percent.

The Faddeev and Jackiw procedure for the quantization of constrained gauge systems is used on the analysis of an interacting electron-phonon model including Chern-Simons term. The generalized FJ brackets of this system with first-class constraints are found by removing the singularity in the symplectic matrix. This was done by adding the gauge-fixing term in the symplectic potential. Compared to Dirac’s method, this Faddeev and Jackiw approach is quite straightforward for these systems.

In this work, we study the collision of two and three Gaussian wave-packets in the fractional quantum mechanics platform. For this purpose, we study the effects of different parameters such as frac...

We show how two-species models, already proposed for the rheology of networks of associative polymer solutions, can be derived from nonequilibrium thermodynamics using the generalized bracket formalism. The two species refer to bridges and (temporary) dangling chains, both of which are represented as dumbbells. Creation and destruction of bridges in our model are accommodated self-consistently by assuming a two-way reaction characterized by a forward and a reverse rate constant. Although the final set of evolution equations for the microstructure of the two species and the expression for the stress tensor are similar to those of earlier models based on network kinetic theory, nonequilibrium thermodynamics sets specific constraints on the form of the attachment/detachment rates appearing in these equations, which, in some cases, deviate significantly from previously reported ones. We also carry out a detailed analysis demonstrating the capability of the new model to describe various sets of rheological data for solutions of associative polymers. ISSN:0148-6055

The classical motion of a particle in a dipolar potential, $U_{\hbox{dip}}(q) = - {k}/{q^2}$, and free motion along a curve in phase space are proven to be equivalent. We also prove that the singularity at $q=0$ in the dipolar potential is strong enough as to prevent the flow of particles from one side of the singularity to the other. This effect does not depende on whether the dipole potential is regarded as attractive ($k>0$) or as repulsive ($k

We have investigated a conjunction of γ-rigid and γ-stable collective motion of odd-A nuclei around the critical point of spherical to axially deformed shape phase transition. Our model is made on even–even nuclei with the [Formula: see text] critical point symmetry that is coupled to a single nucleon in a j orbit. The Davidson potential for the β part is applied to the γ-rigid and γ-stable part of a Bohr–Hamiltonian in the presence of a deformation-dependent mass term and spin-orbit interaction. The solutions provide baselines for odd-mass nuclei with the [Formula: see text] symmetry as Bose–Fermi dynamical symmetry. The level structure and transition patterns for some special j is estimated in detail.

A new analytical model for the current–voltage characteristic of a resonant tunneling diode (RTD) is presented herein, being derived from the basic integral of the Tsu–Esaki equation. The model is physics based and developed as a function of material parameters such as the effective mass, barrier heights, and Fermi levels as well as geometrical parameters such as the barrier height and well width. The material chosen for the double-barrier RTD structure is AlGaAs/GaAs. The dependence of the peak transmission on the applied voltage and the scattering effect in the active region, which are neglected in previous models, are also taken into account. The model is implemented and validated using numerical simulations, revealing that the resulting electrical characteristic is in good agreement with numerical simulations using the Green’s function formalism.

We provide a framework for extending equilibrium local molecular field (LMF) theory to a statistical ensemble evolving under a time-dependent applied field. In this context, the self-consistency of the original LMF equation is achieved dynamically, which provides an efficient method for computing the equilibrium LMF potential, in addition to providing the nonequilibrium generalization. As a concrete example, we investigate water confined between hydrophobic or charged walls, systems that are very sensitive to the treatment of long-ranged electrostatics. We then analyze confined water in the presence of a time-dependent applied electric field, generated by a sinusoidal or abrupt variation of the magnitudes of uniform charge densities on each wall. Very accurate results are found from the time-dependent LMF formalism even for strong static fields and for time-dependent systems that are driven far from equilibrium where linear response methods fail.

In neutron optics, we analyse the propagation of slow (thermal) neutrons along a semi-infinite waveguide limited by a large repulsive potential (reminding the propagation of light along an optical fibre). We set an ideal case of a straight empty two-dimensional semi-infinite waveguide limited by an infinitely repulsive potential (Dirichlet conditions on its boundaries). The neutron wave function is given through an integral representation involving the incoming wave with energyE, Green's function and certain functions defined on the boundaries. The latter functions follow from the Dirichlet conditions, thereby proposing a new formalism in neutron optics. We develop various approximations (through Fourier and Hilbert transforms) and numerical computations. We get: (a) the expected extinction of the incoming wave for very large penetration into the waveguide, (b) the generation of propagation modes and their number for suitably large penetration, asEincreases, (c) an estimate of the critical angle.

We study T-duality with non-zero components of NSNS two form field along directions we dualize with the help of canonical formalism. As a result of this procedure we determine generalized Buscher's rules. We also apply the same procedure to the case of non-relativistic string., Comment: 13 pages

The 4×4 matrix method proposed by Yeh is a robust technique to solve the wave propagation problem in anisotropic media. However, it fails in the isotropic limit. Although the singularity of this me...

The integral equation formalism based reference interaction site model (RISM) molecular solvation theory is applied to pure liquid acetonitrile and water–acetonitrile binary mixtures of different compositions. Solvate formation of d- and f-block ions by ACN is also calculated to check applicability of the RISM theory. The generalized Amber force field (GAFF) and the universal force field (UFF) parameters were found to be suitable for applications with the RISM theory for acetonitrile solvent. The presence of local microsolvated clusters for water–acetonitrile mixtures is validated in the RISM calculations.

A transformation is introduced in momentum representation to keep a covariant description at every stage of a loop computation in gravity. The procedure treats on equal footing local internal and space-time symmetries althought the complete transformation is known for the former [1] whereas in gravity we solve for the first few orders in an expansion. As an explicit application the one loop UV divergences of Hilbert-Einstein gravity with a cosmological constant and spin 0, 1/2 and 1 matter are computed with functional methods and in a field-covariant formalism.

Due to the growing number of publications and applications based on the exploitation of Bloch surface waves and the gross errors and approximations that are regularly used to evaluate the properties of this type of wave, we judge seriously important for successful interpretation and understanding of experiments to implement adapted formalism allowing to extract the relevant information. Through a comprehensive calculation supported by an analytical development, we establish a generalized formula for the propagation length which is different from what is usually employed in the literature. We also demonstrate that the Goos-H\"anchen shift becomes an extrinsic property that depends on the beam dimension with an asymptotic behavior limiting its value to that of the propagation length. The proposed theoretical scheme allows predicting some new and unforeseen results such as the effect due to a slight deviation of the angle of incidence or of the beam-waist position with respect to the structure. This formalism can be used to describe any polarization-dependent resonant structure illuminated by a polarized Gaussian beam., Comment: 38 pages, 11 figures including 3 figures in the Supplemetary Information file

Effects of intrinsic spin-orbit coupling in MoS2 nanotubes are studied for the first time. To this end the double group formalism is applied, yielding model independent information on band/spin spl...

International audience; A novel theoretical non-Hermitian formalism for analyzing nonlinear nano-optics is proposed. Its main strength lies in the unique way it analytically incorporates the quasinormal modes of the nanostructures, which have to be resonantly excited to achieve significant nonlinear efficiency. Owing to the analyticity, the formalism is computationally more effective than the usual multipolar Mie-scattering expansions for nonlinear nano-optics. It is also more general and applies to nanostructures laying on substrates or embedded in thin films. It additionally provides guidelines for the multiparameter design and optimization of nonlinear photonic nanostructures. In particular, it reveals an important phase-matching condition at the subwavelength scale between the linear and nonlinear harmonics, which was not clarified in earlier theoretical works based on Hermitian theory for waveguides and high-Q cavities. Its closed form is a major asset that enables us to propose a systematic approach to design phased-matched nanostructures offering drastic second harmonic generation enhancements with engineered χ(2) and pump beams.

The goal of the present short letter is to prove, through a specific example (i.e., the class of Ricci-flat, Petrov type D geometries), that the original Newman-Penrose (NP) formalism, seen as an exterior differential system (EDS), suffices to provide the needed syzygies and integrals of the EDS under consideration—without (in principle) the aid of a computer algebra system (CAS). © 2020, Pleiades Publishing, Ltd.

We propose a new vertex formalism, called anti-refined topological vertex (anti-vertex for short), to compute the generalized topological string amplitude, which gives rise to the supergroup gauge theory partition function. We show the one-to-many correspondence between the gauge theory and the Calabi--Yau geometry, which is peculiar to the supergroup theory, and the relation between the ordinary vertex formalism and the vertex/anti-vertex formalism through the analytic continuation., 27 pages, 13 figures; v2: typos are corrected, published in JHEP

In this work we investigate the effects of a Fermi velocity modulation in a valley filter in graphene created by a combination of a magnetic and electric barrier. With the effective Dirac equation of the system, we use the transfer matrix formalism to obtain the transmittance. We verify that the valley transport in graphene is very sensitive to a Fermi velocity modulation, which is able to choose which valley will be filtered with perfect filtering. Also, it is possible to use a Fermi velocity modulation to filter both valleys or to make the valley filter transparent. It reveals that the Fermi velocity is a powerful tool that can be used to tune a graphene valley filter, since it has a total control in its transport properties.

The application potential of pristine and monovacant C6BN for sensing gaseous pollutants (CO, CO2, NO, NO2, NH3, H2S, and SO2) is investigated using density functional theory with van der Waals dis...

Phase equivalent potential corresponding to an energy-dependent potential is constructed via the formalism of supersymmetric quantum mechanics and judge the merit of our approach through model calculations.

In the paper we go on a development of effective new chaos geomentry and non-linear analysis technique to studying chaotic features of different naturesystems. We presented the general formalism of the chaos-geometrical appraoch to treating, analysing, modelling and forecasting chaotic dynamics of environmental radioactivity systems. As usually, the approach combines together application of the advanced multifractal formalism, the advanced mutual information scheme, the Grassberger-Procaccia algorythm, the Lyapunov exponent analysis, the method of predicted phase trajectories, the memory functions method, the neural networks algorythms etc.

We provide a brief and comprehensive overview over recent developments in the field of phase-coherent caloritronics in ordinary and topological Josephson junctions. We start from the simple case of a short, one-dimensional superconductor-normal metal-superconductor (S-N-S) Josephson junction and derive the phase-dependent thermal conductance within the Bogoliubov-de Gennes formalism. Then, we review the key experimental breakthroughs that have triggered the recent growing interest into phase-coherent heat transport. They include the realization of thermal interferometers, diffractors, modulators and routers based on superconducting tunnel junctions. Finally, we discuss very recent theoretical findings based on superconductor-topological insulator-superconductor (S-TI-S) Josephson junctions that show interesting heat transport properties due to the interplay between topological band structures and superconductivity., Comment: A topical review invited from EPJ ST Special Issues; 23 pages, 8 figures, 120 references

This paper introduces Hamel’s formalism for classical field theories with the goal of analyzing the dynamics of continuum mechanical systems with velocity constraints. The developed formalism is utilized to prove the existence and uniqueness of motions of an infinite-dimensional generalization of the Chaplygin sleigh, a canonical example of nonholonomic dynamics. The formalism is very flexible and, for mechanical field theories, includes the Eulerian and Lagrangian representations of continuum mechanics as special cases. It also provides a useful approach to analyzing symmetry reduction.

We investigate two well-known approaches for extending the fewest switches surface hopping (FSSH) algorithm to periodic time-dependent couplings. The first formalism acts as if the instantaneous adiabatic electronic states were standard adiabatic states, which just happen to evolve in time. The second formalism replaces the role of the usual adiabatic states by the time-independent adiabatic Floquet states. For a set of modified Tully model problems, the Floquet FSSH (F-FSSH) formalism gives a better estimate for both transmission and reflection probabilities than the instantaneous adiabatic FSSH (IA-FSSH) formalism, especially for slow nuclear velocities. More importantly, only F-FSSH predicts the correct final scattering momentum. Finally, in order to use Floquet theory accurately, we find that it is crucial to account for the interference between wavepackets on different Floquet states. Our results should be of interest to all those interested in laser-induced molecular dynamics.

A nonlinear finite-difference time-domain (FDTD) formalism is developed to model dispersive second-order nonlinear effects in photonic arrangements and optical devices. The dispersion of the second-order nonlinear susceptibility, χ(2), is based on the Faust-Henry model, which makes no implicit assumption on the relationship between the linear and nonlinear dispersion. Unlike other models for χ(2) dispersion, the Faust-Henry model accurately describes a broad range of crystal classes, including the $$ \overline{4}3m $$ crystal class, which is essential to generating radiation in the terahertz frequency regime. As such, the developed formalism based on the Faust-Henry dispersion model overcomes limitations imposed by previous FDTD methods for modelling second-order nonlinear effects.

Operators’ ordering is often employed in almost all calculations of quantum optics. In this paper by virtue of differentiation within ordered product of operators we put forward general differential formalism of normally and anti-normally ordering Bose operators, which seems neat and concise

In this paper, we investigate the stability analysis and the feedback stabilization design problem for multiphase chemical systems using a nonequilibrium thermodynamics formalism. We first present a compartmental model for multiphase systems far from thermodynamic equilibrium. The modeling framework allows us to describe irreversible multiphase systems as a differential-algebraic equation (DAE) system. The differential part of the model corresponds to macroscopic balance equations. The algebraic system of equations represents the interface thermodynamic subsystem that occurs between bulk phases. Integrating the DAE model is equivalent to fixing the degrees of freedom prescribed by the Gibbs phase rule. A linear stability analysis and numerical simulations for the resulting differential-algebraic model are presented. We stabilize the system by fixing the pressure to a constant value. Following this result, we present a feedback structure that fixes the pressure of the system using the proposed modeling framework.

Using the sextic Stroh formalism, we show that the strains and stresses inside an anisotropic elastic parabolic inhomogeneity are uniform when the surrounding anisotropic elastic matrix is subjected to uniform loading at infinity. All of the uniform strains and stresses inside the inhomogeneity are independent of the single geometric parameter characterizing the two-phase structure. In addition, some strain and stress components within the inhomogeneity simply coincide with their remotely prescribed counterparts in the matrix.

This work focuses on the theoretical investigation of the possible coexistence of superconductivity and antiferromagnetism in DyNi2B2C superconductor. By developing a model Hamiltonian for the system under consideration and by employing double time temperature-dependent Green’s function formalism and by applying a suitable decoupling approximation technique, the possible coexistence of superconductivity and antiferromagnetism in DyNi2B2C superconductor has been shown to be a very distinct possibility. The phase diagrams of superconducting gap parameter (Δ) versus temperature (T), the superconducting transition temperature (Tc), and antiferromagnetism order temperature (TN) versus antiferromagnetic order parameter (η) have been plotted. Finally, by combining the two phase diagrams, the possible coexistence of superconductivity and antiferromagnetism in DyNi2B2C superconductor has been demonstrated. The finding is in agreement with the experimental observations.

In the present study, four equations of state (EOSs) were used, namely Birch-Murnaghan, Dodson, Bardeen and modified Lenard Jones for evaluating relative compression volume Vp/Vo, isothermal bulk modulus B and spinodal pressure Psp for C60 under high pressure. Required constant parameters in the EOSs were taken from literature data. Starting from the definition of spinodal pressure, as the pressure at which bulk modulus of a material vanishes (i.e. B=0), A new approach for the evaluation of spinodal pressure have been established, in present work, by extrapolating variation of bulk modulus under high pressure data to the point where B=0, and formulate a new mathematical expression for spinodal pressure. With the aim of finding validity of these equations of state of applying on C60, the calculated results from the entire equations of state are compared with themselves and with other available experimental and theoretical published data. The results for Vp/Vo, B, and Psp are found to be in agreement with each other for whole pressure ranges. Some other theoretical and empirical data are brought in this study and give good agreements with our results. The new spinodal pressure approach and high pressure studies might represent a promising entrance to the formalism of universal equation of state for solids.

In this work, the total energies of doubly excited states (ns2) 1Se, (np2) 1De, (nd2) 1Ge, (nf2) 1Ie, (ng2) 1Ke, and (nh2) 1Me of the helium isoelectronic sequence with Z ≤ 10 are calculated in the framework of the variational method of the Screening Constant by Unit Nuclear Charge (SCUNC). These calculations are performed using a new wavefunction correlated to Hylleraas-type. The possibility of using the SCUNC method in the investigation of high-lying Doubly Excited States(DES) in two-electron systems is demonstrated in the present work in the case of the (nl2) 1Lπ doubly excited states, where accurate total energies are tabulated up to n = 20. All the results obtained in this paper are in agreement with the values of the available literature and may be useful for future experimental and theoretical studies on the doubly excited (nl2) 1Lπ states of two-electron systems.