Modern Physics Letters B

The crystal structure and atomic dynamics (vibrational properties) of the ${\mathrm{\text{Ga}}}_{0.5}{\mathrm{\text{In}}}_{1.5}{\mathrm{\text{Se}}}_3$ compound are studied at room temperature and under normal conditions. The monoclinic symmetry crystal structure of the P6₁ space group is explained by the polyhedral structure. The studies were carried out by the method of Raman spectroscopy. In the spectrum obtained in the frequency range $\nu =0$–800 cm${}^{-1}$, four main vibrational modes were observed: ${\nu }_1=37$, ${\nu }_2=84$, ${\nu }_3=153$ and ${\nu }_4=230$ cm${}^{-1}$. The analysis showed that these modes correspond to the vibration of different polyhedra. Modes ${\nu }_1=37$ and ${\nu }_2=84$ cm${}^{-1}$ correspond to vibrations of bipyramids, and modes ${\nu }_3=153$ and ${\nu }_4=230$ cm${}^{-1}$ correspond to vibrations of tetrahedra.

Waterjet propulsion has many advantages when operating at high-speed conditions. As a special way of navigation, it is mostly used in high-speed ships and shallow draft ships. In this paper, a mixed-flow waterjet pump was taken as the research object. For the two cases of non-uniform inflow and uniform inflow, a modified RANS/LES method was adopted for unsteady calculation of the whole channel, aiming at investigating the influence mechanism of the non-uniform inflow on the energy performance and pressure pulsation characteristics of the waterjet pump. The hydrodynamic characteristics of the waterjet pump were comprehensively analyzed such as head, efficiency, axial-force, internal flow and pressure pulsation. It is found that the non-uniform inflow will reduce the external characteristics of the waterjet pump and lead to the huge fluctuation of energy performance with time. Low-speed swirls occur locally in the intake duct for non-uniform inflow, in which condition the vorticity is much higher than that for uniform inflow. In terms of the low-speed area, $P_{\mathrm{\text{Rey}}}$ and $P_{\mathrm{\text{tur}}}$, the values under non-uniform inflow condition are generally larger than those under uniform flow condition when in the impeller and guide vane zone. The dominant frequencies of pressure pulsation are, respectively, $f_n$, 7$f_n$ and 4$f_n$ in the intake duct, impeller and diffuser, which are almost consitent for the two cases. However, the frequency features are more diverse, and the amplitudes corresponding to the same frequencies are more intense for non-uniform inflow.

Under consideration is a modified Toda lattice system with a perturbation parameter, which may describe the particle motion in a lattice. With the aid of symbolic computation Maple, the discrete generalized $(m,2N-m)$-fold Darboux transformation (DT) of this system is constructed for the first time. Different types of exact solutions are derived by applying the resulting DT through choosing different $m$. Specifically, standard soliton solutions, rational solutions and their mixed solutions are given via the $(2N,0)$-fold DT, $(1,2N-1)$-fold DT and $(2,2N-2)$-fold DT, respectively. Limit states of various exact solutions are analyzed via the asymptotic analysis technique. Compared with the known results, we find that the asymptotic states of mixed solutions of standard soliton and rational solutions are consistent with the asymptotic analysis results of solitons and rational solutions alone. Soliton interaction and propagation phenomena are shown graphically. Numerical simulations are used to explore relevant soliton dynamical behaviors. These results and properties might be helpful for understanding lattice dynamics.

In this paper, we study exact solutions of the (3+1)-dimensional Boiti–Leon–Manna–Pempinelli equation. We employ the Hirota bilinear method to obtain the multi-solitary wave solutions, soliton resonant solutions, periodic solutions and interactional solutions and periodic resonant solutions. The corresponding asymptotic features and images are also clearly given.

In this paper, we give a further discussion of short-distance teleportation. We propose bidirectional, rotation and cyclic rotation teleportation schemes for short-distance participants, respectively. In our bidirectional transmission scheme, the quantum channel is still an EPR pair and an auxiliary qubit in the ground state $|0〉$, and two participants can transmit an unknown single-qubit state to each other. In the rotation and cyclic rotation schemes, bidirectional transmission is performed between two adjacent participants in turn. The unknown state qubits of the participants collapse into the ground state after one bidirectional transmission, and can be used as auxiliary qubits in subsequent bidirectional transmission. After a complete state rotation, each participant has held the unknown state of the other participants, and the last one owned by the participant is still the original unknown state. Although the schemes we proposed are applicable to a small range of transmission, they have certain advantages in saving quantum resources.

This work reports on the fabrication and characterization of a K9 glass planar waveguide structure. The helium ion implantation was employed to form the waveguide on the K9 glass. The choices of the energy of 0.4 MeV and the dose of $6.0\times 10^{16}$ ions/cm² were conducted by the SRIM 2013. The $m$-line spectroscopy and the modal profile of the He${}^{+}$-irradiated K9 glass waveguide were performed by the prism-coupling system and the end-face coupling technique at 0.6328 $\mu$m, which suggests the capability of light propagation. The He${}^{+}$-implanted K9 glass waveguides can serve as potential candidates for advanced integrated optoelectronic devices.

In this paper, we pay attention to the nonlinear dynamical behavior of ultra-short pulses in optical fiber. The new Hamiltonian amplitude equation is used as a governing model to analyze the pulses. We secure the ultra-short pulses in the forms of bright, dark, singular, combo and complex soliton solutions by the utilization of three of sound computational integration techniques that are protracted (or extended) Fan-sub equation method (PFSEM), the generalized exponential rational function method (GERFM), extended Sinh-Gordon equation expansion method (ShGEEM). Moreover, Jacobi’s elliptic, trigonometric, and hyperbolic functions solutions are also discussed as well as the constraint conditions of the achieved solutions are also presented. In addition, we discuss the different wave structures by the assistance of logarithmic transformation. The findings demonstrate that the examined equation theoretically contains a large number of soliton solution structures. By selecting appropriate criteria, the actual portrayal of certain obtained results is sorted out graphically in 3D and 2D profiles. The results suggest that the procedures used are concise, direct, and efficient, and that they can be applied to more complex phenomena. The resulting solutions are novel, intriguing, and potentially useful in understanding energy transit and diffusion processes in mathematical models of several disciplines of interest, including nonlinear optics. Our new results have been compared to these in the literature.

The effects of parameters on nanoscale titanium nitride during the formation process in ferrite were studied via the molecular dynamics (MD) simulation. The formation of titanium nitride was executed by employing a dislocation-motivated formation model in which the atomic diffusion has a significant contribution. The roles of N/Ti atom ratio, temperature and matrix defect were identified and the according nitride formation property was analyzed.

The study of traffic dynamics on couple networks is important for the design and management of many real systems. In this paper, an efficient routing strategy on coupled spatial networks is proposed, considering both traffic characteristics and network topology information. With the routing strategy, the traffic capacity can be greatly improved in both scenarios of identical and heterogeneous node capacity allocation. Heterogeneous allocation strategy of node delivery capacity performs better than identical capacity allocation strategy. The study can help to improve the performance of real-world multi-modal traffic systems.

The radioisotope batteries have drawn extensive attention due to the high energy density. Nowadays, the radioisotope thermophotovoltaic systems are one of the most promising radioisotope batteries. In this work, the crystal emitter design and the associated performance of the radioisotope thermophotovoltaic generators are investigated. First, the design of photonic crystal emitter together with the adoptions of both the multi-layer insulation and supporting materials are discussed. In order to optimize the system efficiency, the effects of the area of emitters are mainly investigated. We have analyzed the efficiency of system using GaSb cells and Si cells, respectively. With Si cells, the system efficiency can computationally reach about $1.4\%$ with an output power of 7 W. When GaSb cells are employed, the system performance is estimated to an efficiency of $12.3\%$ with 61.6 W output.

In this paper, the (3+1)-dimensional constant coefficient of Date–Jimbo–Kashiwara–Miwa (CCDJKM) equation is studied. All of the vector fields, infinitesimal generators, Lie symmetry reductions and different similarity reduction solutions are constructed. Due to the arbitrary functions in the infinitesimal generators, the (3+1)-dimensional CCDJKM equation can further be reduced to many (2+1)-dimensional partial differential equations. The explicit solutions of the similarity reduction equations, which include the quasi-periodic wave solution, the interaction solution between the periodic wave and a kink soliton and the trigonometric function solutions, are constructed with proper arbitrary function selection, and these new exact solutions are given out analytically and graphically.

In this paper, we analyze a mixture of Lognormal and Log-Logistic distribution. We estimate the parameters of the introduced distribution by using the expectation-maximization (EM) algorithm. Various phenomena in the field of medicine and economy could be modeled by this mixture. In this paper, it is used to construct new mortality model for determining the unisex premium rates in life insurance. The application of the model is illustrated in the case of Serbian population and its advantages are presented in the context of life insurance premium calculation.