In this work, we theoretically calculate the transmittance spectra for a one-dimensional photonic quasicrystal composed of a high-temperature superconductor and a semiconductor. The materials are organized based on the Octonacci sequence; in addition, we consider the dependence of dielectric constants and layer thicknesses on the applied pressure. When the temperature increases, the transmittance spectra

This paper retrieves optical fiber Bragg gratings for perturbed NLSE having cubic–quartic dispersive reflectivity with parabolic-nonlocal combo law of refractive index. The Jacobi elliptic function solutions are found using the unified auxiliary equation methodDark solitons, singular solitons, bright solitons, combo singular solitons and combo dark-singular solitons are obtained.

The main aim of this work is to determine and explain the relationships between optoelectronic properties and the sulfur anion content in Cu2ZnSn(SxSe1-x)4 solid solution. Band gap and absorption coefficient are of primary interest to the engineers and scientists researcher worked in optoelectronic field. Herein, the electronic and optical properties are calculated based on 128 conventional atoms within

This article investigates the optical soliton to Lakshmanan–Porsezian–Daniel (LPD) model in birefringent fibers which incorporates two vector solitons. The optical solitons in the forms of bright, dark, singular, as well as combined form bright-dark, dark-singular, complex soliton and multiple soliton solutions are extracted successfully by the mechanism of Fan-extended sub equation approach with the

In this report, we present the use of surface-enhanced Raman scattering (SERS) in combination with the silver nanodendrites (AgNDs) for direct detection of melamine at low concentrations in liquid milk and infant formula. The fern-like AgNDs were electrochemically deposited onto the surface of silicon. The results showed that the molecular fingerprints of melamine in liquid milk and infant formula

Ultrathin Cu(InGa)Se2 (CIGS) material has become one of the emerging material in the research of solar cell fields due to its excellent optical, electrical and tunable bandgap properties. In this study, we have described a numerical simulation of ultrathin CIGS solar cell using SCAPS-1D program tool based on WS2 as a buffer layer, CIGS as an absorber layer with a-Si/MoTe2 as a hole transport layer

In a recent study, the authors proposed an optical broadband angular reflector having a band selective feature and high reflectivity rate for possible applications in photovoltaic applications using a binary photonic crystal. The obtained 100% reflectivity regions for TE and TM modes were in bandwidths of 244 nm and 134 nm, respectively. In this paper, we show theoretically the enhancement of the omnidirectional

A three suspended-cores fiber (TSF) is proposed. Different to the traditional three-bridge suspended-core fiber, TSF has three suspended-cores with an air-hole in the center. The mode coupling in TSF is analyzed based on the effective area, and the TSF are optimized to support LP01 mode at both C and L wavelength bands and the LP01 mode has only weak coupling between each fiber core. Due to asymmetry

In this article, we present classification of integrated optical MEMS devices as being free-space or guided-wave based on light propagation method. Free-space optical MEMS devices are limited in performance by precision of micromachining and alignment of optical components. To fully leverage the capacity of the free-space devices, integration of photonic or electronic signal processing on chip is a

Laser precision cutting process of phenolic resin plates (PRP) has attracted widespread attention, but at this stage, this work is carried out without understanding the hazards of process by-products and process mechanism. Here, mechanism of PRP ultraviolet (UV) nanosecond laser precision cutting process has been assessed based on by-product composition analysis. Composition of solid residue in cutting

This article reports a theoretical study of the intersubband optical properties in quantum wells with modified Manning potential considering the effects of position-dependent effective mass. Calculations are made in the effective mass and parabolic band approximations. The electronic spectrum, dipole matrix element for intersubband transitions, optical absorption coefficient, and refractive index coefficient

Aiming at the shortcomings of traditional point cloud registration algorithms, a point cloud initial alignment method based on the differential evolution algorithm is proposed. By designing an appropriate fitness function and selecting a proper evolution strategy, the probability and speed of finding the globally optimal solution are improved. Finally, the point to plane iterative closest point is

In the printing quality inspection, measuring the primary color ink content of printed products is an important link. In order to obtain accurate measurement results in the ink content measurement system, this study preprocesses the interference information such as stray light and noise in the collected ink content spectrum information of cyan, magenta, and yellow samples firstly. Considering the limited

In this paper, scattering of the electromagnetic waves from a metal elliptical cylinder covered by a plasma layer is investigated by the Finite Element-Boundary Integral (FE-BI) method. The under study object that can be supposed as an elliptic complex antenna is located in a constant magnetic field. The inner cylinder can be rotated to plasma cover so that they are nonconfocal. Generally, elliptic

In a recent paper (Khokhlov, 2016), a protocol was proposed for using weak measurement to attack BB84. This claimed the four basis states typically used could be perfectly discriminated, and so an interceptor could obtain all information carried. We show this attack fails when considered using standard quantum mechanics, as expected — such “single-shot” quantum state discrimination is impossible, even

In this article, abundant optical soliton solutions of the Biswas–Milovic equation with Kudryashov’s law and nonlinear perturbation terms in polarization preserving fibers is constructed by employing two improved analytical schemes, namely, the improved Sardar sub-equation method (IMSSEM) and the improved generalized Riccati equation mapping method (IGREMM). As a result of these improved approaches

At present, due to the advantages of non-contact, fast response, high precision, etc., the realization of temperature sensing technology based on the fluorescence intensity ratio has become the focus of the research field of temperature measurement. Here, we successfully prepared Bi3+ and Eu3+co-doped luminescence material and studied its temperature sensing performance. The absolute sensitivity and

We propose the non-uniformly polarized vortex (NUPV) beams with the changing retardation angle and the tunable angle between polarization and radial direction, in which the radially polarized vortex (RPV) beam is a particular case. Based on the paraxial vector theory, the analytical propagation expressions of NUPV beams in uniaxial crystals orthogonal to the optical axis are derived and used to investigate

In light of the problem of low precision and time consuming in indoor three-dimensional positioning of visible light communication (VLC), we propose an indoor three-dimensional positioning system of VLC based on improved immune particle swarm optimization (IIMPSO) algorithm. To reduce the influence of reflection, we select the optimal field of view by analyzing the indoor multipath effect, and improve

Electric field enhancement of the plasmonic tip-based nanofocusing light field determines the interaction efficiency of light and matter. Herein, the nonlinear/liner nanofocusing of the plasmonic tips array (PTA) is quantitatively analyzed, under excitation of the radial vector beam (RVB) and the linear polarization beam (LPB), respectively. Second harmonic (SH) emission intensity of PTA, under ultrafast

The present work proposes an optical polarization based reflection technique for determining surface roughness of metal surfaces. A linearly polarized light beam is used to illuminate the sample surface and two intensity data frames are recorded with specific orientations of an analyzer. An algorithm is developed to combine the pair of intensity data frames captured with this simple setup. Assuming

A laser ultrasonic method based on guided waves was proposed to characterize delamination defects in Cu/Al composites. Simulation analysis was used to analyse to the propagation characteristics of laser ultrasound. The delamination defects made the mode of laser ultrasound change from surface wave to guided wave. The influences of delamination size on guided waves were analyzed to investigate the interaction

In this paper an antenna with dynamically controllable radiation pattern direction, in the low THz frequency band, is designed and investigated. The radiating element is composed of a rectangular patch antenna on a grounded dielectric while, radiation pattern control is made possible through applying a superstrate, inspired by metasurface structures, with gap of 25μm from the antenna surface. The radiating

Optical BICs are investigated of a Si3N4 slab perforated with cross-shape nanohole array. BICs at normal incident angle and oblique incidence are both be found in this nanostructure by adjusting the nanohole shape and size and refractive index of the surrounding medium. Q-factor at at-Γ BIC and at off-Γ BIC can be more than 106, which indicates light is confined in this nanostructure perfectly. High

As is known to all, the complex nonlinear Fokas-Lenells equation is widely used to describe the propagation of short pulses in optical fibers. In this work, we aim to study its time-space fractional modified form. An ancient Chinese algorithm called the Ying Bu Zu Shu (盈不足术), which is from an ancient Chinese mathematics monograph-The Nine Chapters on the Mathematical Art (九章算术) in about second century

Optically, unit sphere S2 is illustrated to be a 2-sphere in space with positive curvature. In this paper, we construct a new characterization for spherical electric and magnetic flow density of spherical Ss−magnetic flows of particles by the spherical frame in S2 spherical space. Thus, we get some new optical conditions of spherical Ss−magnetic electric and magnetic phase by using spherical magnetic

The physical description of the dynamic speckle behind biological tissues is often unknown or not known at all. In this paper, we investigate the application of the variational mode decomposition in dynamic speckle sequences. The proposed VMD indexes are used to adaptively determine the bands related to the dynamic speckle sequence, which can obtain more selective information about the characteristics

Nanocrystalline CdS semiconductor was synthesized by electrodeposition technique, and characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM), and FTIR spectroscopic methods. XRD analysis result showed that it is a hexagonal crystal structure. SEM micrographs showed that the CdS nanocrystal is homogeneously distributed on the surface. The roughness of the CdS

Influence of K+ ion concentrations on the upconversion emissions of LiYF4: Yb, Er phosphor has been investigated. Li1-xKxY0.77F4:Yb0.2, Er0.03 phosphors are synthesized by solid-state reaction method under reduced atmosphere. X-ray diffraction analysis revealed a major phase transition from tetragonal LiYF4 to hexagonal KYF4 as the concentration of K+ ion increases. Blue, green and red upconversion

This paper deals with laser-arc hybrid welding of high nitrogen steel with 1.2 mm diameter filler wire. The effect of nitrogen content in the weld on the microstructure and properties was analyzed. Results show that as the nitrogen content in the weld increases, ferrite growth is inhibited and the average hardness of the weld increases. As the nitrogen content in the weld increases, the tensile strength

Loop-closure detection plays an important role in visual simultaneous localisation and mapping;it is an independent part of the visual odometer and can effectively reduce its accumulated error, in addition to helping with loop-closure detection for relocalisation. With the development of deep learning methods in recent years, the training models of convolutional neural networks for major data sets

Fabrication and characterization of a fiber optic surface plasmon resonance (SPR) based phosphate ion sensor utilizing the coating of cobalt oxide (CoO) over the gold coated unclad core of the fiber have been carried out. The interaction between CoO layer and incoming phosphate ion changes the effective refractive index of the CoO layer which affects the resonance wavelength in the SPR spectrum. The

Recently miniaturization, integration and high sensitivity are becoming the mainstream of the development of pressure sensing technology. This paper proposes a pressure sensor realized with the microring resonator on a cantilever beam. The performance of the pressure sensor is theoretical analyzed and then simulated using finite element modeling. It shows that the cantilever beam substrate can greatly

A simple configuration of a photonic crystal fiber (PCF) with dual-core is proposed that utilizes surface plasmon resonance (SPR) to work as a refractive index (RI) sensor. The PCF structure is asymmetric; thus, the PCF shows birefringence. A plasmonic metal layer of gold is placed over the fiber sensor to form an analyte channel externally. The sensing range and sensitivity are extended by investigating

The intermodal entanglement in a two-channel symmetric nonlinear coupler, operated with Kerr nonlinearity was investigated using the analytical method based on the Heisenberg picture in quantum mechanics. The Heisenberg equations of motion of the propagating modes were solved based on the Baker-Hausdorff (BH) formula. The entanglement expressions were then derived following the Hillery-Zubairy criteria

In this paper, the propagation of partially coherent vortex beams in gain media was investigated based on the generalized Huygens-Fresnel principle. Our research focused on the influences of topological charge (m) and coherence length (σ0) on light intensity distribution, phase and spectral degree of coherence during the propagation. The results show that partially coherent vortex beams can maintain

As the third pole of the earth, Qinghai Tibet Plateau breeds many unique species; their population size, living environment and migration process have been observed and studied by many researchers. However, these observations are mainly carried out in summer with UAVs when the temperature is high, while they are hard to work in winter since the harsh environment such as low temperature and strong wind

In this article, the modified direct algebraic method is applied for the perturbed nonlinear Schrödinger equation (NLSE) describing the dynamics of optical solitons in metamaterials, in the presence of quadratic–cubic nonlinearity. Various types of solutions are extracted such as bright solitons, singular solitons, dark solitons, singular periodic wave solutions, periodic wave solutions, plane wave

We demonstrated an all-fiber phase noise measurement technique to detect transient phase variation of polarization maintaining Yb-doped fiber amplifier based on active phase locking of an optical heterodyne detection system. The root mean square, power spectral density, and drift velocity in the phase noise were analyzed for both core-pumped single clad fiber amplifier and clad-pumped double-clad fiber

A conventional thermal evaporation technique has been used for thin film preparation of Se40As60−ySy (y = 0, 10, 20) chalcogenide materials. Optical characterization has been done in the wavelength range of 600–2700 nm in the thin films of above mentioned materials. Various optical parameters like refractive index, extinction coefficient, dielectric constant, dielectric loss, absorption coefficient

In this work, Ag2WO4/BiOCl composite photocatalyst was successfully prepared by a facile coprecipitation. The crystalline structures, morphologies, optical properties and photocatalytic activities of photocatalysts have been investigated via XRD, SEM, EDX spectrum, UV–vis diffuse reflectance spectroscopy, PL spectra and electrochemical measurement. After depositing Ag2WO4 onto the surface of BiOCl

The accurate recognition of the burning state of cement rotary kiln is of great significance to improve the qualified rate of clinker quality, ensure the safe operation of rotary kiln and reduce the production coal consumption of enterprises. In this paper, a recognition method of the burning state of cement rotary kiln based on Otsu-Kmeans flame image segmentation and support vector machine (SVM)

Using a bilinear transformation and the variable separation approach, The abundant localized structures for the (2+1)-dimensional NLS equation of PT-symmetric media are explored. And Some special soliton solutions such as periodic soliton solution, dromion solutions, ring, peak, breathers and instantons type of solitons are presented by selecting the different functions appropriately. and then, the

Based on the Vernier effect and the Sagnac interference characteristics of polarization-maintaining photonic crystal fibers, a separate pressure sensing structure using an F-P cavity to enhance sensitivity is proposed. The experiment results show that using 40.2 cm long polarization maintaining photonic crystal fiber as the sensing element, the pressure sensitivity of the sensitizing structure at 1560 nm

Owing to the eigenstates of orbital angular momentum (OAM) are infinite and orthogonal to each other, OAM can improve communication capacity infinitely. In this paper, we propose a terahertz vortex beam generator on transmissive metasurfaces. When the y-polarized terahertz wave illuminates vertically to the metasurface along the -z direction, the proposed metasurface generates terahertz vortex beams

In this paper, theoretical and experimental analysis has been done for the beam transmission of 2.2 GHz RF signal by 1X8 linear phased array antenna fabricated in S-band. The proposed architecture is based on true time delay optical beam forming network which gives squint free beam steering of RF signal. The optical beam forming network is based on chirp fiber Bragg grating (CFBG) and multiple lengths

In this paper, near zone scattering properties of a perturbed perfect electromagnetic conductor (PEMC) cylinder are observed using the perturbation theory (PT). The analytical solution of the scattered field is obtained for both the transverse electric (TE) and transverse magnetic (TM) polarizations of the incident field. The perturbed cross section is generated considering the limits imposed by the

In this paper, we introduce a new characterization of spherical electric and magnetic flow density of magnetic spherical Heisenberg SHα particle by spherical frame in spherical Heisenberg space SH32. Thus, we get some new optical qualifications of magnetic spherical Heisenberg SHα electric and magnetic phase by using spherical magnetic fields. Also, we demonstrate spherical electric and magnetic flow

Herein, the structural, optical, dielectric and optical conductivity parameters of the CdBr2/SiO2 interfaces are reported. Thin films of CdBr2 are coated with 50 nm thick SiO2 under a vacuum pressure of 10-5 mbar. The structural morphological and optical investigations have shown that CdBr2 exhibit hexagonal structure of lattice parameters of a=b=7.20Å and =13.86 Å, energy band gap of 3.32 eV and Urbach

A novel Al-doped (3 wt%) ZnO (AZO) UV photodetector (PD) and ZnO/AZO heterojunction double-layer UV PD were prepared on a polyethylene terephthalate (PET) substrate by utilizing the radio frequency (RF) sputtering technology and conventional photolithography. Because the ZnO/AZO heterojunction possesses the ability to improve the separation of the photogenerated electron-hole pairs, the responsivity

Regular inspection of rail wear is very important to ensure the safety of railway transportation. Rail profile registration is a key step in rail wear measurement. However, the accuracy of rail profile registration cannot be guaranteed due to soil and corrosion on the rail waist. To solve this problem, a new rail profile registration method based on probability iterative closest point algorithm with

The current paper obtains soliton solutions to the governing nonlinear Schrödinger's equation that is considered with Kudryashov's arbitrary form of refractive index along with two forms of nonlocal nonlinear forms of nonlinearity. A complete spectrum of soliton solutions have been recovered. This is accomplished by the aid of modified Kudryashov's method together with an addendum to it. The existence

8-hydroxyquinolin-1-ium 4-aminobenzenesulfonate solution was synthesized via conventional chemical method. Different spectroscopies techniques utilized to characterize the new organic salt molecule. The spatial self-phase modulation technique was employed to obtain the nonlinear optical parameters of the new salt. The diffraction ring patterns used to deduce the nonlinear refractive index (10−6 cm2/W)

We obtained a twisted far field with rectangular hollow distribution by designing a new type of light source, which can rotates around the axis during propagation. Then, we derived the expression of cross spectral density function on propagation of such source and analyzed the characteristics of spectral intensity distribution of beam field. In addition, we discussed the influence of corresponding

The temperature dependences (or shifts) of spectral lines 4I13/2→4I15/2 in GaAs: Er3+ and v5→v1 in Y3Al5O12:Yb3+ crystals are studied by using an approximate processing based on a full expression. This expression contains both the static effect owing to lattice thermal expansion and the dynamic effect coming from electron-phonon interaction. The static effect is evaluated from the pressure shift of

In this work we present a generalized nonlinear (3+1)-dimensional Sasa–Satsuma equation. This equation is influenced by nonlinearity and spatial dissipations effects in all spatial directions. We formally retrieve bright and dark optical soliton solutions for this higher dimensional Sasa–Satsuma model. In addition, other singular and exponential solutions of distinct structures are derived.

A Tm,Ho:YVO4 laser with compact geometry was demonstrated and analyzed. For the continuous wave laser, the slope efficiency of 30.5% was achieved. By inserting a Cr:ZnS saturable absorber into the cavity, the passively Q-switched laser generated almost constant pulse duration of 83 ns with the slope efficiency of 19.3%. The pulse energy was also independent of the pump power, around 130μJ. Through

Contrast improvement as well as detail preservation is important for human visualization in image enhancement. Traditional histogram equalization methods are easy to produce over-enhancement results, resulting in the loss of fine details. In order to deal with this problem, this paper proposes an image enhancement scheme (called as global–local image enhancement, GLIE) based on weighted least squares