International Journal of Modern Physics B

We theoretically, demonstrate a high delay bandwidth product (DBP) and zero group velocity dispersion (GVD) in a two-dimensional one-way slow light waveguide. The waveguide consists of gyromagnetic photonic crystal (GMPC) and a cladding formed by silicon photonic crystal. At the edge of the band, weak interactions (“semi-anticrossing”) between the chiral edge state (CES) mode and the mode localized at the surface of cladding are observed. The group velocity of CES wave can be tuned by adjusting the modal field distribution. As a result, an extraordinarily large value of normalized DBP of 0.63 with a group index of 10.32 and a bandwidth ranging from $0.529(2\pi c/a)$ to $0.562(2\pi c/a)$ is obtained. This result may contribute to one-way slow light applications in information communication systems.

Based on the Hadamard operator and Bell states, an identity-based public-key quantum signature scheme is proposed. In our scheme, the signer’s identity is used as her public key. Her private keys are generated by the trusted private key generator (PKG). Given a quantum signature, the verifier can verify the validity of the quantum signature by the signer’s identity information without any public-key certificate. So, our quantum signature has the advantages of the identity-based signature system. On the other hand, in our scheme, it need not use the long-term quantum memory. The verifier need not perform any quantum swap test or state comparison algorithm. What is more, our quantum signature is secure against PKG’s forgery attack. And the disputation of losing quantum signature can be arbitrated by PKG. Therefore, our scheme is relatively more practical and efficient than the similar schemes.

In this work, superhydrophilic surfaces are obtained on LY12 aluminium alloy by irradiation of femtosecond (Fs). First, based on the theory of laser induced surface plasmon polariton, the formation mechanism of micro-nano structures is analyzed. Then the periodic change of the micro-nano structures with different wavelength and incident angle is calculated. According to the theoretical results, the structure period is 600 nm at the vertical incident and incident wavelength with 800 nm, and the experimental results agree with the theoretical results. Furthermore, two different kinds of postprocessing methods are employed to change the superhydrophilic surfaces to superhydrophobic surfaces. All the micro-nano structures are tested by scanning electron microscope (SEM), contact angle (CA) and Fourier transform infrared spectra (FTIR). By analyzing the function of the functional groups of C–H, C–F and C–O, the transition mechanism of the surface from superhydrophilicity to superhydrophobicity is also explored.

In this paper, we have presented the analytical analysis of integrable perturbed nonlinear Schrödinger (PNLSE) equation with third-order dispersion (TOD) in Kerr media using our newly proposed technique, extended modified auxiliary equation mapping method. By the implementation of this technique, we have obtained a variety of some new families and more general form of exact traveling wave solutions including triangular-type solutions, periodic and doubly periodic-like solutions, combined soliton-like solutions, kink and anti-kink type soliton-like solutions using three parameters which is the key difference of our newly proposed method. PNLSE is a well-known governing model to study the propagation of optical solitons in nonlinear optical fibers and other telecommunication networks with a type of Kerr law nonlinearity. This particular type of nonlinearity originates when a light wave in an optical fiber is subjected to nonlinear responses. For graphical representation of our newly found results, we have presented them with detailed dynamical physical representation using Mathematica 10.4 to explain in a more efficient manner the behavior of different physical structures of solutions. Also, the computational work and efficiency of the method demonstrate the reliability, straightforwardness, and simplicity of the technique for solving other nonlinear complicated partial differential equations.

Essential protein plays a crucial role in the process of cell life. The identification of essential proteins not only promotes the development of drug target technology, but also contributes to the mechanism of biological evolution. There are plenty of scholars who pay attention to discover essential proteins according to the topological structure of protein network and biological information. The accuracy of protein recognition still demands to be improved. In this paper, we propose a method which integrates the clustering coefficient in protein complexes and topological properties to determine the essentiality of proteins. First, we give the definition of In-clustering coefficient (IC) to describe the properties of protein complexes. Then we propose a new method, complex edge and node clustering (CENC) coefficient, to identify essential proteins. Different Protein–Protein Interaction (PPI) networks of Saccharomyces cerevisiae, MIPS and DIP are used as experimental materials. Through some experiments of logistic regression model, the results show that the method of CENC can promote the ability of recognizing essential proteins by comparing with the existing methods DC, BC, EC, SC, LAC, NC and the recent UC method.

By using the transfer matrix method (TMM), we theoretically explore the transmittance properties and cutoff frequency of one-dimensional photonic crystal (1DPCs) within the terahertz frequency region. The present structure consists of high-temperature superconductor and semiconductor layers. The results of the calculations represent the effects of various parameters on the cutoff frequency. We have used the two-fluid model as well as the Drude model to describe the permittivity of superconductor and semiconductor. Further, we consider that the permittivity of both the materials is depending on the hydrostatic pressure. The present results show that with the increasing of different parameters as the operating temperature, the thickness of semiconductor, and the filling factor of semiconductor, then the cutoff frequency shift to lower frequencies regions. By the increasing of superconductor thickness, hydrostatic pressure, doping concentration and filling factor of the superconductor, we found the cutoff frequency shifts to higher frequency regions. These results indicate that cutoff frequency can be modified through these different parameters. Finally, the present design could be useful for many optical systems as the optical filter, reflector and photoelectronic applications in the Terahertz regime.

Entering big data era, individual GPS trajectory data have created great opportunities for human mobility and collective behavior studies. Individual GPS trajectories can be collected by location-based services on mobile phones. However, GPS data often do not record transportation modes (e.g., walking, riding a bus, or driving a car). In this study, we analyzed the statistical characteristics of individual trajectories and present a collaborative isolation forest (Co-IF) model to identify the transportation modes of mobile phone GPS trajectories. Unlike previous models that identify multiple transportation modes simultaneously, the proposed Co-IF model builds a single-class classifier for each transportation mode and then combines their results. Compared to the existing models, the Co-IF model offers competitive performance and shows improved reliability with noisy trajectories.

A scheme of quantum teleportation using Jaynes–Cummings model is proposed. It consists of using a partial entangled state generated from the interaction between a two-level atom and single mode of radiation field as a quantum channel. By controlling the number of photons inside cavity and detuning parameter, the dynamical evolution of quantum correlation and entanglement degree in terms of quantum discord and concurrence, respectively, in the nonresonance case are investigated. Moreover, a comparative study between the teleported entanglement, teleported quantum correlation and average fidelity shows a good similarity between their dynamical evolution. Consequently, we conclude that quantum discord may be considered as a good information source in quantum teleportation process.

This paper presents an optimum design for highly birefringent micro structured photonic crystal fiber (PCF). This is designed with novel hexagonal PCF of honeycomb lattice cladding with hexagonal shaped air cavities and the kernel of the hive is formed by two oblong air holes. The dispersion characteristics of this novel structure have been analyzed analytically using Finite Element Method (FEM) and reported for dispersion and nonlinear coefficient including other fiber parameter. This structure is optimized with distinctive parameters of fiber geometry like pitch of the core, diameters of elliptical shaped air cavities, cladding region having ample of space assortment of wavelength from 0.1 m to 2.0 m also made of SF57 glass helps in reaching high birefringence and low dispersion through the optimization of the arrangement and diameter of elliptical and hexagonal air holes. The proposed model has been suggested with high nonlinearity for super continuum generation.

Various non-classical continuum mechanics models appearing in previous studies cannot perfectly explain the mechanical properties of micro- and nanomaterials. Establishing a reasonable continuum mechanics model that comprehensively reflects the scale effect on material deformation is of great practical significance for objectively explaining the variation law of mechanical properties of micro- and nanomaterials under the combined action of different scale effects. Based on nonlocal strain gradient theory, a new scale-dependent model is proposed for axially moving nanobeams. In this study, an asymptotic expansion is performed using the multiscale time method to obtain the amplitude-frequency response curve of the equilibrium solutions for the forced vibration problem. Afterwards, the effects of various system parameters, especially the scale parameters, on the resonance curve are examined. Finally, the effects of nonlocal parameters and material characteristic length parameters on the amplitude-frequency response curves are investigated through typical numerical examples. The numerical results show that the nonlocal parameters promote the emergence of the main resonance, whereas the material characteristic length parameters suppress the emergence of the main resonance. Moreover, these parameters also affect the response amplitude and the skewness and jumping point of the amplitude-frequency characteristic curve.

This paper investigates the soliton wave on a free-moving fluid surface by studying the two-fluid model, which are the fourth-order Boussinesq and the modified Liouville equation. This study depends on one of the computational schemes to find exact and soliton wave solutions of these models. These solutions give novel physical properties of these waves, which enable their use in many fluid applications. In order to achieve our goal, the $exp(\pm \mathrm{\Phi }(\xi ))$-expansion method is applied to these two models, and for more explanation of the physical properties of these models, some of the obtained solutions are sketched in different forms (two, three-dimensional and contour plots). Moreover, the obtained results are discussed for its novelty and how it changed from that achieved in the previous work.

Understanding the behavior of excess Ga is important for fabrication methods that employ the sputtering of GaSb-based materials. This is due to the comparatively low vapor pressure of Ga, which can result in GaSb becoming Ga-rich under experimental conditions. In this study, the growth and characterization of nonstoichiometric polycrystalline GaSb thin films with excess Ga, grown by RF magnetron sputtering, are reported. Ga content was adjusted by mixing N₂ in the Ar sputtering gas. The structural properties indicate that the grown thin films maintain the zinc blend structure of GaSb, and have an induced tensile strain along a direction parallel to the substrate. Excess Ga segregates towards the film surface and forms micro/nanoclusters. The internal tensile strain and the Ga cluster formation have little effect on the intrinsic properties of GaSb. These findings could lead to the fabrication of GaSb-based thin films using sputtering with excellent mass productivity.

Based upon the optical coherence superposition principle, a system to acquire light transmitted by a single-multimode fiber has been built. By collecting the optical interference images and using MATLAB software for analysis, the target light transmitted by a single-multimode optical fiber can be extracted from it. Thus, the transmission characteristics of light in a single-multimode optical fiber can be obtained, aiming to realize the direct transmission imaging through the multimode optical fiber by the compensation principle according to the change of phase in the transmission process and to provide technical support for the development of medical examination and medical devices in China.

The hydrodynamic forces acting on a quantized vortex in a superfluid have long been a highly controversial issue. A new approach, originally developed in the astrophysical context of compact stars, is presented to determine these forces by considering small perturbations of the asymptotically uniform flows in the region far from the vortex in the framework of Landau–Khalatnikov two-fluid model. Focusing on the irrotational part of the flows in the Helmholtz decomposition, the classical Kutta–Joukowski theorem from ordinary hydrodynamics is thus generalized to superfluid systems. The same method is applied to predict the hydrodynamic forces acting on vortices in cold atomic condensates and superfluid mixtures.