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Highlights: [•] CNFs-based flexible transparent conductive paper was successfully prepared. [•] Optoelectronic properties of paper can be controlled by the times of LbL assembly. [•] Transparent conductive paper has good optoelectronic properties. [•] Transparent conductive paper has excellent flexibility and mechanical properties. [ABSTRACT FROM AUTHOR]

Progress in glass science has given rise to innovative functional glasses, unlocking significant applications for creating cutting-edge materials such as solid-state batteries, solar cells, optical reinforcement, and medical technologies. In this study, rice husk silica, Bismuth (Bi) and Tin (Sn) oxide ores were used to fabricate a novel glass series. The electrical conductivity (i.e., dielectric constant) of the glasses increased with the dopant's gravimetric levels. The novel glass series also possesses good optical non-linearity with metallisation criteria ranging from 0.35 to 0.40, which points to a novel non-linear optical material. The non-bridging oxygen content in the new glasses exceeds the bridging oxygen, indicating high polarisation. The transmission coefficient decreased with increasing dopant concentration from 0.76 to 0.75, while the reflection loss decreased from 0.37 to 0.38. For the Caesium-137 energy, GS6 has a minimum HVL of ∼5.02 cm, which is ∼20 % lower than that of commercial Pb/Ba glass. For the two energies, GS6 has the least MFP, suggesting that the addition of dopants improved the efficiency of the glass attenuation. Process capability analysis based on Caesium-137 (661.7 keV) and overall performance analysis of the fabricated glass series revealed that GS3 glass (15 wt% dopant) is the optimal material, even outperforming the commercial Pb/Ba glass. Although Cobalt-60 (1253 keV) yielded comparable outcomes, concentrations beyond 15 wt% in GS3 showed marginal enhancements in the photon attenuation parameters of the glasses. Hence, the fabricated GS3 and the circular synthesis method of the glasses are cost-effective for low-energy gamma/X-ray shielding. The percentage deviation between the experimental data for MAC and that of Monte Carlo simulations for Cs-137 and Co-60 energies are both within 10 %, which validates the methods of this paper. [ABSTRACT FROM AUTHOR]

Abstract: A new precision reclaim design process using micro-electroetching (MECE) as a removal process for indium-tin-oxide (In2O3SnO2) nanostructure removal from the surface of polyethylene terephthalate (PET) digital paper is presented. The design features of the removal process for In2O3SnO2 and the tool design of the sphere-form cathode are of major interest. A cathode with a large diameter and a small gap-width between the cathode and the PET-film are advantageous in achieving a fast feed rate. A small end radius of the sphere-form cathode, a pulsed direct current, a higher electrolyte concentration or temperature, or a higher cathode rotational speed can be used to achieve a higher etching rate for In2O3SnO2. Through the ultra-precise etching of the nanostructure, the optoelectronic semiconductor industry can effectively reclaim defective products, thereby reducing production costs. A validity evaluation of the In2O3SnO2 removal in MECE is constructed in the current study. [Copyright &y& Elsevier]

Perovskite light-emitting diodes (PeLEDs) are widely used in optoelectronics due to their excellent performance. The hole transport layer (HTL) plays a crucial role in the performance of the device. In this paper, we prepared quasi-two-dimensional perovskite light-emitting diodes with doping CsBr into PEDOT:PSS as a composite HTL, and investigated the optoelectronic properties of the devices. The maximum luminance of the CsBr-doped device was 6652 cd/m2 and the maximum current efficiency (CE) was 7.55 cd/A, which were increased by 112 % and 80 % compared with the undoped device, respectively. This is primarily due to the PEDOT:PSS/CsBr composite HTL optimizes the morphology of the perovskite film, passivates the defects of the perovskite film, and suppresses the exciton quenching at the HTL/perovskite emission layer (EML) interface. Meanwhile, CsBr doping helps to enhance the hole transport ability of HTL and thus increase the exciton recombination efficiency, which improves the device performance. The results in this paper can provide experimental support for the development of PeLEDs. • Optimized the hole transport layer (HTL) and prepared quasi-two-dimensional perovskite light-emitting diodes by doping CsBr into PEDOT:PSS. • Enhanced PL strength, suppresses exciton bursting at the HTL/emission layer (EML) interface. • Passivation of defects in perovskite films and enhancement of crystallinity. • Enhanced hole injection ability and exciton recombination efficiency in HTL. • Optimized PeLED's performance is improved in every way. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study on the effect of pressure on the structural, elastic, electronic, thermoelectric, and optical properties of vacancy ordered double perovskite Cs 2 SeCl 6 , using first principle calculations. Results show that the lattice constant and band gap of Cs 2 SeCl 6 decrease with increasing hydrostatic pressure from 0 to 140 GPa. The band gap value decreases from 2.94 eV to 1.62 eV and the electronic structure analysis reveals an indirect band gap nature. The elastic constants, Poisson's ratio, and Pugh's ratio indicate the mechanical stability and ductile behavior of Cs 2 SeCl 6. Furthermore, due to its suitable band gap and enhanced light absorption with increasing pressure, Cs 2 SeCl 6 exhibits potential as a photoelectric absorption layer material for high-pressure solar cell applications. Moreover, Cs 2 SeCl 6 exhibits high electrical conductivity and low thermal conductivity, resulting in a high figure of merit and promising thermoelectric applications. [Display omitted] • This paper comprehensively explores the impact of pressure on Cs 2 SeCl 6 perovskite. • Pressure decreases lattice constant and band gap to 8.45 Å and 1.62 eV respectively. • Poisson's and Pugh's ratios confirm ductile behavior, with pressure enhancing it. • At room temperature, ZT peaks of Cs 2 SeCl 6 surpass 0.7 across all pressure levels. • Applied pressure boosts electrical conductivity while lowering thermal conductivity. [ABSTRACT FROM AUTHOR]

LiGd(MoO 4) 2 has been investigated due to its optoelectronic applications, especially for development of light-emitting diodes. In the present paper, LiGd(MoO 4) 2 single crystals grown by Czochralski method was studied in terms of structural and temperature dependent optical properties. X-ray diffraction analysis showed that the crystal crystallizes in a single phase tetragonal structure. Raman spectrum exhibited six distinguishable peaks around 207, 319, 397, 706, 756 and 890 cm−1. These peaks correspond to vibrational modes of free rotation, symmetrical stretching, symmetric bending, antisymmetric stretching and antisymmetric bending of (MoO 4)2− tetrahedron. Infrared transmittance spectrum had eight minima around 2114, 2350, 2451, 2854, 2929, 2960, 3545 and 3578 cm−1 which are due to multiphonon absorptions. Spectral change of transmittance curves at various temperature between 10 and 300 K was utilized to elucidate temperature effect on absorption characteristics. Optical band gap of the material was found using Tauc and spectral derivative methods. The band gap value was obtained as 3.09 eV at room temperature and this value increased to 3.22 eV with decreasing temperature down to 10 K. The detailed analysis on the temperature dependency of the band gap was applied by Varshni model. The band gap at 0 K and change of rate of the band gap were estimated as 3.23 eV and −1.45 × 10−3 eV/K, respectively. Room temperature photoluminescence spectrum of the crystal presented a peak around 709 nm which corresponds to red light emission. LiGd(MoO 4) 2 is a potential candidate for optoelectronic devices emitting red light. [ABSTRACT FROM AUTHOR]

In this paper, we synthesized and investigated the structural, optical, and electrical properties of spin-coated zinc-tin-oxide thin films with varying molar ratios and total precursor concentrations for photocatalytic applications. The structural studies were carried out using XRD and Raman spectroscopy. XRD and Raman analysis confirms that all the polycrystalline films are composed of ZnO and Zn 2 SnO 4 mixed phases. UV–Vis and fluorescence spectroscopy were used to investigate the optical properties and estimate the band gap of the thin films. Dual absorption edges are observed in the UV–Vis absorption spectra of films prepared with a Zn/Sn = 2 M ratio. Photoluminescence studies confirm the dominated near band edge (NBE) emission for films prepared with a Zn/Sn = 2 M ratio. The electrical resistivity and Hall Effect measurement were carried out on all the studied compositions. The Haacke's figure of merit (FOM) is found to be in the range of 3 × 10−6 to 9 × 10−7 for the studied samples. The as-grown films were subjected to photocatalytic degradation studies using methyl orange (MO) dye under UV light irradiation. We achieved MO degradation efficiency as high as 80% in less than 90 min. [ABSTRACT FROM AUTHOR]

Background: Due to the high susceptivity of the walking pattern to be affected by several disorders, accurate analysis methods are necessary. Given the complexity and relevance of such assessment, the utilization of methods to facilitate it plays a significant role, provided that they do not compromise the outcomes.Research Questions: This paper aimed at identifying the standards for the application of adaptive predictive systems to gait analysis, given the extensive research on this field. Furthermore, we also intended to check whether such methods can effectively support clinicians in determining the number of physiotherapy sessions necessary to recover gait-related dysfunctions.Methods: Through a screening process of scientific databases, we considered studies encompassed from 1968 to April 2019. Within these 50 years, we found 24 papers that met our inclusion criteria. They were analyzed according to their data acquisition and processing methods via ad hoc questionnaires. Additionally, we examined quantitatively the adaptive approaches.Results: Concerning data acquisition, the included papers presented a mean score of 6.1 SD 1.0, most of them applying optoelectronic systems, and the ground reaction force (GRF) was the most used parameter. The AI quality assessment showed an above-average rate of 7.8 SD 1.0, and artificial neural networks (ANN) being the paradigm most frequently utilized. Our systematic review identified only one study that addressed therapeutics including a predictive method.Significance: While much progress has been identified to predict assessment aspects, there is little effort to assist healthcare professionals in establishing the rehabilitation duration and prognostics. Therefore, future studies should focus on accomplishing the production of applications of predictive methods to therapeutics and prognosis, not lingering extremely on the analysis of gait features. [ABSTRACT FROM AUTHOR]

Single crystal (SC) MAPbBr 3 and MAPbCl 3 perovskite are considered promising materials for fabricating high-performance photodetectors (PDs) due to their impressive optoelectronic properties and good chemical stability. Structural modification of PDs is the fundamental solution to improve performance. In this paper, we designed a simple structure diagram considering photoelectric properties and the possibility of epitaxial crystal growth. Then a solution height restriction method (SHR) was used to grow the crystal and make the internal secondary excitation feasible. X-ray rocking curves (XRC) of MAPbBr 3 -SHR SCs show the quality of crystal under this growth method is excellent. X-ray photoelectron spectroscopy (XPS) measurements and Energy-dispersive X-ray spectroscopy (EDS) indicate element diffusion exists in the interface. Photoluminescence spectra (PL) and the photoelectric performance test have proved the existence and validity of the internal secondary excitation of crystals. Based on the above analysis, it was demonstrated that the inner MAPbCl 3 single-crystal enhances the optoelectronic performance of MAPbCl 3 -MAPbBr 3 crystals by the internal secondary excitation effect. [ABSTRACT FROM AUTHOR]

In developing countries, the deployment of medical diagnostic technologies remains a challenge because of infrastructural limitations (e.g. refrigeration, electricity), and paucity of health professionals, distribution centers and transportation systems. Here we demonstrate the technical development and clinical testing of a novel electronics enabled microfluidic paper-based analytical device (EE-μPAD) for quantitative measurement of micronutrient concentrations in decentralized, resource-limited settings. The system performs immune-detection using paper-based microfluidics, instrumented with flexible electronics and optoelectronic sensors in a mechanically robust, ultrathin format comparable in size to a credit card. Autonomous self-calibration, plasma separation, flow monitoring, timing and data storage enable multiple devices to be run simultaneously. Measurements are wirelessly transferred to a mobile phone application that geo-tags the data and transmits it to a remote server for real time tracking of micronutrient deficiencies. Clinical tests of micronutrient levels from whole blood samples ( n =95) show comparable sensitivity and specificity to ELISA-based tests. These results demonstrate instantaneous acquisition and global aggregation of diagnostics data using a fully integrated point of care system that will enable rapid and distributed surveillance of disease prevalence and geographical progression. [ABSTRACT FROM AUTHOR]

• Photon absorption and excitation of perovskite can be controlled by ultrafast laser. • Main mechanism of ultrafast laser processing perovskite is photochemical reaction. • Optoelectronic device of perovskite can be prepared and optimized by ultrafast laser. Perovskite materials have attracted widely interest in the study of their physical mechanisms and applications due to variable special structures, a wide variety of organic-inorganic compounds, and excellent photoelectric properties such as high carrier mobility and high quantum luminescence efficiency. Ultrafast laser with the characteristics of ultrafast and ultrastrong has been another research hotspot in recent years. Ultrafast laser processing mainly relies on cold processing, and the perovskite devices prepared by this method have the characteristics of small heat affected zone, superior performance, and good stability. In this paper, the latest studies in the processing of perovskite materials by ultrafast laser are reviewed, divided into two parts: (i) the interaction of ultrafast laser with perovskite materials and the changes of perovskite physical properties irradiated by ultrafast laser; (ii) the ultrafast laser-assisted perovskite-based devices for luminescence, storing optical information, converting optical signals, optical imaging. Finally, the development, application and industrialization of perovskite materials in the field of optoelectronics are prospected. [ABSTRACT FROM AUTHOR]

Highlights • A fully reconfigurable on-chip photonic signal processor. • Dispersive Fourier transform and linearly chirp modulation are used for operation. • Arbitrary mathematical operation is performed on incident optical signal. • Operation time of 200 ps with high resolution of 300 fs. Abstract This paper introduces the concept of on-chip temporal optical computing, based on dispersive Fourier transform and suitably designed modulation module, to perform mathematical operations of interest, such as differentiation, integration, or convolution in time domain. The desired mathematical operation is performed as signal propagates through a fully reconfigurable on-chip photonic signal processor. Although a few numbers of photonic temporal signal processors have been introduced recently, they are usually bulky or they suffer from limited reconfigurability which is of great importance to implement large-scale general-purpose photonic signal processors. To address these limitations, this paper demonstrates a fully reconfigurable photonic integrated signal processing system. As the key point, the reconfigurability is achieved by taking advantages of dispersive Fourier transformation, linearly chirp modulation using four-wave mixing, and applying the desired arbitrary transfer function through a cascaded Mach-Zehnder modulator and a phase modulator. Numerical simulations of the proposed structure reveal a great potential for chip-scale fully reconfigurable all-optical signal processing through a bandwidth of 400 GHz. [ABSTRACT FROM AUTHOR]

An elementary theory of using the definition of work function in photoelectric effect to determine precise and reliable work function by contributing frequency to optical-electric yield is investigated in this paper. On account of the theory of Fermi-Dirac distribution as well as the definition of work function proposed by Einstein in photoelectric effect, a representative mathematical approach is applied to analyze the frequency-based optical-electric yield in quantitatively terms. Supplementing applications to In 14 cluster and three kinds of metals, the simulations agree well with the observed spectra (photoelectric yield-frequency). At the same time, the threshold frequency of light-dependent the work function is theoretically explained successfully via one equation so that the work function can be predicted precisely and reliably. The consequences provide that the formalism pursed in this paper, which is straight forward and practical, could play a significant role in studying metal cluster spectroscopy. The experimental results in this paper may hopefully promote overall analysis on theoretical basis. They may further analyze the usability of bulk-derived models to cluster photo-ionization activity, and the conversion of molecular or atomic form into surface photoemission form. [ABSTRACT FROM AUTHOR]

Nanopaper defined as a sheet made of cellulose nanofibers has recently attracted a growing interest in paper-based flexible and transparent sustainable transistors, electronics, devices and sensors. Use of bacterial cellulose nanopaper, particularly in optical sensing platforms, is becoming increasingly popular owing to its numerous desirable properties. Herein, we propose a carbon quantum dots-embedded paper-based sensor for selective iodide sensing. To this aim, the nanopaper was obtained by an environment-friendly approach using bacterial cellulose made of nanofibers (the diameter of nanofibers was observed as 40 ± 10 nm), which were produced by A. xylinum . Then, nitrogen-doped carbon quantum dots were embedded into nanopaper to gain photoluminescence properties. The obtained photoluminescent nanopaper was cut into circular pieces for easily handling, or rectangular pieces for use in a disposable wax-printed paper-based microcuvette which could be inserted in a common spectrofluorometer. Finally, the nanopaper pieces were used for anion sensing and we obtained a selective detection of iodide in seawater (as a model real sample media). Limit of detection (LOD) and limit of quantification (LOQ) values were respectively calculated as 48 and 144 μM (6.1 and 18.3 ppm) for microcuvette application in seawater. [ABSTRACT FROM AUTHOR]

In this paper, based on a graphene-like BGe monolayer (Appl. Mater. Interfaces 2021, 13, 29,764–29769), we built the armchair and zigzag photodetectors and studied linear and circular photogalvanic effects (PGEs) in two devices. It was found that the produced photocurrents in the armchair and zigzag BGe photodetectors show the cosine and sine relations on double times of polarized angle for the incident light, respectively. Moreover, the vacancy- and substitution-doping can enlarge the generated PGE in two BGe photodetectors by 10–100 times due to the decreasing of symmetry from D 3h to C 2v. Furthermore, the armchair and zigzag BGe photodetectors are all polarization-sensitive for their high extinction ratios, which are larger than those of photodetectors based on multiple two-dimensional materials. This work manifests great potential applications of the BGe monolayer on PGE-driven photodetectors in high performance and low energy-consumption optoelectronics and nanoelectronic devices. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). This article has been retracted at the request of the Editor-in-Chief. The authors have plagiarized part of a paper that had already appeared in the Journal of Optoelectronical Nanostructures, Summer 2016/Vol. 1, No. 2, Page 39–46 ( http://jopn.miau.ac.ir/article_2047_20a5bdcec580d4b33b8c737082427a40.pdf ). One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. [ABSTRACT FROM AUTHOR]

This paper obtains optical soliton solutions to the governing nonlinear Schrödinger's equation that is studied with spatio-temporal dispersion. The integration algorithm that is employed in this paper is the modified simple equation method. This leads to dark and singular soliton solutions that are valuable in the field of optoelectronics. The soliton solutions appear with all necessary constraints that are deemed necessary for them to exist. There are four types of nonlinear fibers studied in this paper. They are Kerr law, power law, parabolic law and the dual-power law. [ABSTRACT FROM AUTHOR]

Field analysis of ring resonator modulators based on p-i-n diodes has been dissected in this paper. This analysis is performed in time and frequency domains. The conformal transformation method has been used for solving 3-D wave equation. Coupling coefficient between the ring and straight waveguides are obtained by developing the coupled-mode assumption. In the resonant wavelength of 1573.91 nm, a drop of more than 15 dB in frequency spectrum of the device has been observed. Time domain simulation shows that this modulator could support up to 0.4 Gb/s and up to 1.5 Gb/s for NRZ and RZ signals, respectively. Obtained simulation results in both domains have been properly complied with experimental results. Main goal of this paper is to present an optimized model from aforementioned modulator. It will be shown that frequency response could be more optimum than original device by optimizing structure parameters. In order to obtain practical values, Firefly Algorithm (FA) is used because it finds optimum points locally. In optimized modulator, extinction ratio (ER) could be increased up to 32 dB which is double than original modulator. [ABSTRACT FROM AUTHOR]

[Display omitted] • We have investigated the effect of amines on the optical properties of 2D perovskites. • The 2D perovskites are synthesized by adopting the ligand assisted reprecipitation (LARP) technique. • By varying the amines, we have observed various shapes like quantum dots, cubic shape and nanorods depend on the length of the carbon chain attached to the benzylamines. • The optical properties also vary with the different benzyl amines, the absorption peak of less carbon chain length benzyl amine perovskites showed at shorter wavelength compared to the long alkyl chain benzyl amines. • The PLQY and lifetime are high with the long carbon chain benzyl amine perovskites 4TBAHD and 3 TFMBAHD. Due to environmental stability issues and the presence of lead in high-performing 3D perovskites and organic 2D perovskites have emerged as excellent light-harvesting materials and gained immense attention for optoelectronic applications such as perovskite solar cells (PSCs) as a capping layer as well as a light-harvesting material. In this paper, we have investigated the effect of varying the type of aromatic amines (benzylamines) and alkyl chain length (hexadecyl and tetradecyl substituted benzylamines), incorporated into organic halide 2D perovskites, on their optoelectronic properties. We synthesized the 2D perovskites were synthesized by adopting the ligand assisted reprecipitation (LARP) technique and analysed their optical properties by using the UV–Visible and Photoluminescence, structural composition using thin-film XRD and morphology analysis using scanning and transmission electron microscopy (SEM and TEM). Our experimental finding suggests the formation of various shapes such as quantum dots, cubic shapes and nanorods which depend on the length of the carbon chain attached to the benzylamines. [ABSTRACT FROM AUTHOR]

The thickness of semiconductor thin films stands as a pivotal parameter dictating their operational efficacy, directly shaping their applications in the realms of electronics and optoelectronics. Nevertheless, the quandary of measuring the thickness of widely utilized hundred-micron-scale semiconductor wafers continues to vex researchers. Existing measurement techniques grapple with issues of inadequate precision, poor stability, and sluggish measurement speeds. To surmount this challenge, this study innovatively devises a method employing reflective spectral fitting technology for film thickness measurement coupled with adaptive correction. This approach integrates an enhanced frequency fitting technique, endowing it with the capability for swift and stable measurements of hundred-micron-scale semiconductor thin films. Simultaneously, addressing measurement errors stemming from complex environmental factors in industrial production, the paper proposes a thickness correction method based on carrier interference principles. This correction method ensures precise thickness calibration even when the sample isn't perfectly perpendicular to incident light, significantly augmenting measurement accuracy and stability. Experimental data demonstrates that employing the proposed methodology enhances measurement accuracy by approximately 50 % and elevates measurement stability by about 80 % compared to existing methods. Particularly noteworthy is its capability to maintain high measurement precision and stability even when the sample isn't entirely perpendicular to incident light. The calibrated measurements exhibit around a 55 % reduction in error compared to uncorrected results. This study presents an efficient and accurate solution for the challenging task of measuring hundred-micron-scale semiconductor thin film thickness in industrial settings. [ABSTRACT FROM AUTHOR]

Herein, the vanadium pentoxide (V 2 O 5) powder and barium titanate (BaTiO 3) nanoparticles (NPs) were incorporated (1 wt % each) into the polyvinyl alcohol (PVA) matrix to fabricate a flexible film using the solution casting. Structural, morphological, elemental and chemical analysis were performed. The UV visible investigations showed a significant drop in the direct bandgap (5.04–2.61 eV), enhancement in the refractive index (1.05–1.95 at 400 nm), excellent rise in the optical conductivity (2.7 × 109 to 1.2 × 1012 S m−1 at 400 nm) after incorporation of V 2 O 5 /BaTiO 3 NPs into the PVA matrix. The frequency response analysis showed a good rise in the dielectric constant (1.1–3.8 at 1 MHz) and a drop in the dielectric loss (5.4–3 at 10 MHz). Thermal analysis also indicated modifications. Enhancements were found in Young's modulus (210–374 MPa). The fabricated PVA/V 2 O 5 /BaTiO 3 nanocomposite film might be a potential candidate for optoelectronic devices. [ABSTRACT FROM AUTHOR]

Based on the superior properties of g-CN and GaGePS monolayers, this paper investigates the optoelectronic properties of the g-CN/GaGePS van der Waals heterostructure under strain and external electric field modulation using density functional theory. The results show that g-CN/GaGePS heterostructure has a type II band alignment and possesses an indirect band gap of 0.986eV, which exhibits enhanced absorption in the visible and ultraviolet range. Under the application of a biaxial strain of 7 %, the g-CN/GaGePS heterostructure undergoes a transition from type II to type I. Furthermore, the electric field not only modulates the g-CN/GaGePS band gap, but also induces band alignment (type II to type Ⅰ) and an indirect gap to direct gap transition. The absorption in the visible range is enhanced by a positive electric field, whereas a negative electric field exerts the opposite effect. A negative electric field enhances UV range absorption. These results suggest that the g-CN/GaGePS heterostructure has prospective applications in optoelectronic devices. [ABSTRACT FROM AUTHOR]

The present paper aims at presenting linear and nonlinear optical properties of Bi 12 GeO 20 single crystals grown by Czochralski method. Transmission and reflection measurements were performed in the 400–1000 nm region. The recorded spectra were analyzed considering well-known optical models. Spectral dependencies of absorption coefficient, skin depth, refractive index, real and imaginary components of dielectric function were presented. The analyses performed on absorption coefficient showed direct bandgap and Urbach energies as 2.56 and 0.22 eV, respectively. The first- and third-order nonlinear susceptibilities and nonlinear refractive index of the crystal were also reported in the present work. The results of the present paper would provide valuable information for optoelectronic device applications of Bi 12 GeO 20. [Display omitted] • Linear and nonlinear optical characteristics of Bi 12 GeO 20 single crystal were reported. • Spectral dependencies of different optical parameters were plotted in the 1.24–3.1 eV range. • The direct band gap and Urbach energies were obtained as 2.56 and 0.22 eV, respectively. • Oscillator strength, dispersion and single oscillator energies were reported. • Nonlinear refractive index, first- and third-order nonlinear susceptibilities were calculated. [ABSTRACT FROM AUTHOR]

The domain of optoelectronics has wide scope and plays a major role in the design of smart electronics for real-world applications. In this paper we propose a WO 3 based Field Effect Transistor (FET) device that functions as a phototransistor. The proposed device consists of 80 nm thin film of WO 3 deposited using Radio Frequency (RF) sputter deposition technique. The synthesized material was characterized to investigate structural, morphological and optical properties. The fabricated FET exhibits ambipolar behaviour and it provides a great response for making a promising device for photo sensing applications. The proposed WO 3 -FET based phototransistor presents the photo-to-dark current ratio (PDCR) in the order of 10 under 650 nm illumination. Furthermore, the device shows repeatable results with higher stability. Additionally, the remarkable advantage proposed in this paper is the device being wafer scalable which increases the competence for mass manufacturing the devices. • This paper presents scalable fabrication process for WO 3 based phototransistor. • Proposed device structure offers 2 mA/W responsivity and 1010 Jones detectivity. • Developed process for phototransistor is scalable and highly repeatable. • FET based photo sensing device pave a silent feature towards optical applications. [ABSTRACT FROM AUTHOR]

A novel angle-ended fiber integrated into the optoelectronic tweezers (OET) chip is proposed to trap large amounts of cells or microorganism from liquid medium. The spotlight from the multimode fiber, which has a core diameter of about 40 μm and an oblique angle of 40 degrees, is used instead of LCD or DMD to generate non-uniform electric field. The fabrication process and method relative to angle-ended fiber is also described in this paper. The light wave based on finite element method (FEM) can calculate the propagation of refracted light into the fluid. The present paper describes the theoretical principles underlying such as electric and fluid field, and describes a simple mechanical analysis based on molecular dynamics for capturing of the flowing cells. The results indicated that optically induced dielectrophoresis (ODEP) force exerted on the red blood cells to drive them moving on the bottom of the OET chip when the velocity of cells are 50 μm/s. Meanwhile, it is possible to develop angle-ended fiber array to form a few virtual electrodes in OET chip rather than a single fiber. Finally, the device expected to show good results from imitating internal blood flow of human organs in the lab on a chip. [ABSTRACT FROM AUTHOR]

Controlling light interactions with matter on the nanometer scale provides for compelling opportunities for modern technology and stretches our understanding and exploitation of applied physics, electronics, and fabrication science. The smallest size to which light can be confined using standard optical elements such as lenses and mirrors is limited by diffraction. Plasmonic nanostructures have the extraordinary capability to control light beyond the diffraction limit through an unique phenomenon called the localized plasmon resonance. This remarkable capability enables unique prospects for the design, fabrication and characterization of highly integrated photonic signal-processing systems, nanoresolution optical imaging techniques and nanoscale electronic circuits. This paper summarizes the basic principles and the main achievements in the practical utilization of plasmonic effects in nanoparticles. Specifically, the paper aims at highlighting the major contributions of nanoparticles to nanoscale temperature monitoring, modern “drug free” medicine and the application of nanomaterials to a new generation of opto-electronics integrated circuits. [ABSTRACT FROM AUTHOR]

This paper introduces a new geometric error modeling approach for multi axes system (MAS) based on stream of variation (SOV) theory, especially for multi-axis precision stage. SOV is used for measuring product quality for some complicated multi operations system, which is widely used in error propagation in engineering field. This paper introduces SOV concept into geometric error modeling for MAS. Instead of different process in manufacture, the new error modeling approach regards each axis as a station in MAS, and calculates the deviations after each station which is considered as upstream factor to next station. It is clear to observe how geometric errors give influence and how deviations accumulate. Different with conventional methods which are only used for error compensation in machine tools, the new error model is beneficial for sensitive error control and optimal configuration selection in design part. In addition, the new error modeling has some merits such as debugging easily due to observe the deviations after every station. A case study of new error modeling procedure for six-axis stage (SAS) in optoelectronic packaging system (OPS) is developed, and applications related to error reduction order and optimal configuration selection are processed based on the new error model. [ABSTRACT FROM AUTHOR]

• Chemical bath-deposited CdS films show an optical energy band gap of 2.42 eV. • The CdS films show optical transmission of 75 % in the 500–900 nm wavelength range. • We have studied the wavelength dependence of photoconductivity of these CdS films. • Photoconductivity peaks at 492 nm showing an electrical energy band gap of 2.52 eV. • Annealed CdS films show improved conductivity, carrier concentration, and mobility. This paper presents a comprehensive study of the optical transmission, photoconductivity, and morphology of CdS thin films deposited via the chemical bath deposition (CBD) method. The films deposited for 60 min exhibit an optical energy band gap value of 2.42 eV and the highest optical transmission of 75 % in the wavelength range of 500–900 nm. For these films, the transmission electron microscopy imaging shows a distribution of particle sizes around 10 nm. The wavelength dependence of the photoconductivity, extracted from photo resistivity data, shows that the maximum photoconductivity occurs at 492 nm wavelength. This corresponds to an electrical energy band gap of 2.52 eV, which is greater than the optically measured energy gap of 2.42 eV. Based on these results, the electron-hole pair binding energy for CdS films is estimated as 100 meV. According to the electrical resistivity vs. temperature measurements, the activation energy is 1.26 eV which agrees with the electrical energy band gap of 2.52 eV. CdS films annealed under nitrogen gas at 200 °C for one hour exhibited an energy gap of 2.32 eV. These films displayed a conductivity of 60 × 10−4 Scm−1, a carrier concentration of 6.38 × 1014 cm−3, and a mobility of 7.46 cm2 V−1 s−1. These impressive characteristics suggest the suitability of CBD-grown CdS films annealed at 200 °C in nitrogen gas, to be used as the window material in CdS/CdTe thin film solar cells and other optoelectronic applications. [ABSTRACT FROM AUTHOR]

In the current paper, we investigate the optical and dielectric properties of the SnMnSe nanocubes. The Sn 0.5+x Mn 0.5−x Se (x = 0.375, 0.250, 0.125, 0) samples are prepared by simple hydrothermal method with the variation of the Sn and Mn concentration. The X-ray diffraction study shows that all the prepared samples are polycrystalline in nature. The average crystallite size increases along with the dislocation density and the average strain value with the increase in the Mn concentration. The morphology shows the formation of nanocubes. The average size of the cubes increases with the increase of Mn content. The reflectance data demonstrate the decreasing order of absorption edges with the increase of Mn content in the sample. The variation of the absorption edges with Mn content tends to decrease the optical bandgap by creating more disorder and defects between the gap region. Broad orange-red photoluminescence emission is observed for all the samples with 532 nm excitation. The electrical study of the sample shows high resistance values. The dielectric behavior as a function of frequency and temperature is investigated, and parameters like dielectric constant, AC conductivity, impedance spectroscopy, and electric modulus are deeply analyzed. The dielectric properties are useful for energy storage applications. All the above optical and dielectric properties of the SnMnSe matrix have potential use in the field of optoelectronics and dielectric applications. [Display omitted] • SnMnSe nanocubes were synthesized by a facile one-step hydrothermal method. • Increase in Mn content leads to decrease in reflectance and increase in bandgap. • The morphology shows nanocubes with size of ∼478 nm. • Dielectric constant and loss tangent increased with increase in temperature. • AC conductivity shows thermally controlled behaviour at low-frequency regions. [ABSTRACT FROM AUTHOR]

This paper synthesized six low-dimensional organic-inorganic hybrid metal halides by a solvothermal synthesis method in a methanol solution environment. This series of compounds exhibit broadband emission covering the entire visible spectra, with significant Stokes shift and long luminescence lifetime, and shows a tunable optical band gap ranging from 2.39 to 3.36 eV. [Display omitted] • Six new low-dimensional hybrid halides were synthesized by a solvothermal method. • This series of compounds exhibit broadband emissions covering the visible light range. • This series of compounds exhibit wide-bandgap tunability from 2.39 to 3.36 eV. In recent years, low-dimensional organic-inorganic metal halides have been widely used in photoluminescent diodes, solar cells, lasers, photodetectors, and other fields because of their rich structures and excellent optoelectronic properties. In this paper, organic cations H 2 DAB (DAB = benzidine) and H 2 TMB (TMB = 3, 3′, 5, 5′-tetramethylbenzidine) are used as structural templates and cations to regulate the structure of inorganic anions (0D, 1D) and then regulate the luminescence properties of the materials. Among them, the materials with one-dimensional inorganic structures show typical semiconductor behavior, and their electrical conductivity increases with the increase of temperature. The inorganic part of this series of compounds has large structural distortion, large bandgap, significant Stokes shift, and wideband emissions. It has a long fluorescence lifetime, ranging from nanosecond to millisecond. More interestingly, they realize the controllable adjustment of the colour of fluorescent light emitted from yellow-green light, yellow light, orange-red light to near-white light. This work provides a new structure model for understanding the structure-activity relationship between structure and luminescence properties. [ABSTRACT FROM AUTHOR]

Abstract: This article has focused on the behavior of strain produced in the III-nitride based multilayer nano-heterostructure such as GaN/AlGaN, InN/AlInN, and InN/GaInN. Moreover, the variations in the strain with different material compositions for the proposed structures have also been reported. In this paper, the eight band k.p method has been utilized to compute the strain produced due to lattice mismatch between the binary and ternary semiconducting thin epitaxial layers in the multilayer nano-heterostructure. The strain has been simulated for entire model of size 288nm, but the significant strain has been observed only in the quantum region that lies between 100nm and 188nm. For all models under simulation, the strain in the quantum region is found to be tensile along both x and y directions, while compressive in nature along z-direction. The correlation between strain and bandgap for the structures has also been reported. The Results presented in the paper may be beneficial for entire nano-optoelectronics community. [Copyright &y& Elsevier]

Abstract: In this paper, an innovative sensor for the control of a tendon-driven mechatronic system is presented. The proposed sensor measures the tendon tension using optoelectronic components properly selected and mounted on a suitably designed compliant frame. This solution presents several advantages mainly in terms of simplicity and compactness with respect to force sensors based on strain-gauge or Bragg-grating. By exploiting the properties of optoelectronic components with a narrow angle of view and by means of a very simple conditioning electronics, the very small deformation of the compliant frame caused by the tendon force can be measured. Moreover, the compliant frame has been designed to allow the sensor to be mounted in any position along the tendon. The sensor working principle, an optimal design procedure and the results of an experimental testbench where two of the proposed sensors are used for the feedback control of a tendon-driven mechatronic system are reported in the paper. The experimental verification of a contact force estimation algorithm useful for grasping and manipulation purposes in which the data collected by the optoelectronic tendon force sensors are exploited is also reported in the paper. [Copyright &y& Elsevier]

Abstract: Thin material laser perforation improves the flexibility and quality of materials such as tipping paper, medicated sticking plaster and breathable plastic film for storage. Perforation processing requires reliable, high speed, robust and adaptable optoelectronic systems to provide controllable permeability and flexibility in thin materials. This article provides descriptions on the design and performance of a new laser perforation system developed to meet such stringent requirements. This system is applicable for on-line thin material perforation. The optoelectronics include a continuous wave CO2 laser whose beam can be modulated into sequences of pulsed laser beams by a mechanical chopper. The focusing characteristics of a real laser beam in the perforation system have been investigated. This allowed laser beams to be focused on the moving thin material to be perforated and adaptable software control to provide the desired pattern distribution of the circular holes perforated on this material. A galvanometer scanner system allows sequential scanning of pulsed laser beams. This unique optoelectronic, mechanical and dedicated embedded control system has been designed and implemented to synchronize the actions of mechanical choppers, galvanometer scanners and the movement characteristics of the thin material. A practical implementation of the sticking plaster and tipping paper laser perforation system has been completed and successfully tested. Results show for example that circular holes with two geometrical distribution patterns are achievable, and unique patterns of perforation can be designed to discourage counterfeiting. [Copyright &y& Elsevier]

Abstract: Contract capacity setting for industrial consumer with self-owned generating units (SOGUs) is a highly discrete and nonlinear optimization problem considering expenditure on the electricity from the utility and operation costs of the SOGUs. This paper proposes an improved Taguchi method that combines existing Taguchi method and particle swarm optimization (PSO) algorithm to solve this problem. Taguchi method provides fast converging characteristics in searching the optimal solution through quality analysis in orthogonal matrices. The integrated PSO algorithm generates new solutions in the orthogonal matrices based on the searching experiences during the evolution process to further improve the quality of solution. To verify feasibility of the proposed method, the paper uses the real data obtained from a large optoelectronics factory in Taiwan. In comparison with the existing optimization methods, the proposed improved Taguchi method has superior performance as revealed in the numerical results in terms of the convergence process and the quality of solution obtained. [Copyright &y& Elsevier]

Abstract: A novel time domain method and its implementation in a simple smart impedance sensor controlled by an 8-bit microcontroller is presented in the paper. The method is based on stimulation of a voltage divider consisting of a resistor working as a current-to-voltage converter and the impedance sensor by a single square-voltage pulse with a duration time T directly generated by the output of the microcontroller and on sampling the resulting voltage on the sensor at three different selected moments T/8, T/2 and 7T/8 by the internal ADC of the microcontroller. The sensor is modeled by a three-components circuit. The duration time T is determined by the first timer and the ADC is triggered by the second timer of the microcontroller. The measurement procedure takes less than 1ms and the determination of model component values is based on basic calculus. Thanks to this, smart sensors basing on this solution are energy-saving, they can work on the same batteries by a few years, and low cost on the level tens euros. Hence, they can be used in wireless sensor networks, especially basing on the ZigBee protocol. The results of the simulation investigation and the experimental verification of the method are included in this paper. [Copyright &y& Elsevier]

In this paper, mid-wave infrared photodetection based on an InAs/GaSb type-II superlattice p-i-n photodetector grown directly on Si substrate is demonstrated and characterized. Excitation power dependence on integrated intensity from the photoluminescence measurements reveals a power coefficient of P ∼ I0.74, indicating that defects related process is playing an important role in the predominant recombination channel for photogenerated carriers. At 70 K, the device exhibits a dark current density of 2.3 A/cm2 under −0.1 V bias. Arrhenius analysis of dark current shows activation energies much less than half of the active layer bandgap, which suggests that the device is mainly limited by surface leakage and defect-related generation-recombination, consistent with the photoluminescence analysis. The detector shows 50% cutoff wavelength at ∼5.5 µm at 70 K under bias of −0.1 V. The corresponding peak responsivity and specific detectivity are 1.2 A/W and 1.3 × 109 cm∙Hz1/2/W, respectively. Based on these optoelectronics characterization results, reduction of defects by optimizing the III/V-Si interface and material growth quality are argued to be the main factors for performance improvement in this Si-based T2SL detector towards low cost, large-format MWIR detection system on Si photonics platform. [ABSTRACT FROM AUTHOR]

In this paper we present the First-principles calculations, established on the density functional theory (DFT) by using generalized gradient approximation (GGA) and ultra-soft pseudo-potential (USP), study to investigate Magnesium (Mg) doping outcome on the different properties of SrZrO 3. The impacts on electronic structure and hence optical properties from Mg-doping have been explored and are reviewed in detail by implementing the conception of TDOS and PDOS. Replacement of Strontium (Sr) atom by Mg tunes the electronic band structure quite significantly with the emergence of new states at Gamma point. Due to this SrZrO3 indirect band gap is transformed to the direct one for Mg-doped SrZrO 3. The density of states for Mg-doped in SrZrO 3 relocate themselves at slightly lower energies and there is strong interaction between Mg-atom and its surrounding atoms is observed. Furthermore, at the conduction band bottom and partial density of states of SrZrO 3 change appreciably and hence we conclude that the electronic band structure is affected by Mg-doping. The optical properties of the un-doped and doped SrZrO 3 are investigated and are correlated with electronic structure. The enormous variation in optical properties and band gap (i.e indirect to direct) by doping of Mg declares this material as attractive contender for optoelectronic materials. [ABSTRACT FROM AUTHOR]

Simulated absorption spectra of twelve donors based on D-π-D (a) and D-π-A-π-D (b) topologies with the Solar Flux for AM 1.5G. • A comparative analysis of different shapes (star, π, H and X) and different topologies (D-π-D and D-π-A-πD) molecules is done. • DFT and TD-DFT calculations has been carried out to know their optical and charge transfer properties. • On the basis of results, we suggest best performing donor materials for organic solar cells. As substantial building units, different shapes and topologies enhance optical and electronic properties. Hence, in this paper, twelve anisotropic molecules of different shapes (star or S, π and H) based on D-π-D and D-π-A-π-D topologies have been designed and investigated theoretically applying a double overlapping wave band strategy for organic photovoltaic applications. This analysis indicates that stronger electron withdrawing A1 fragment, D-π-A-π-D topology, star and π shaped molecules impart toward lower LUMO and smaller Eg values than those of D-π-D type and X or H- shaped molecules. According to TD-DFT calculations, start-shaped molecules show broader spectra with intense peaks in both topologies covering not only visible region but also IR region of spectrum. Furthermore, the optical analysis also demonstrates that π-π* absorptions in short and middle wavelength region are because of central anisotropic multibranched donor (Bi)n-2DF-(Bi)n moiety, where A components exhibit absorptions in the ML wavelength region of spectrum. In General, smaller λ e and λ h values are exhibited for star and π-shaped molecules because of better dimensionality, whereas H and X-shaped (D1b) display more or less similar values. The predicted electron and hole mobility values for DAD1-S are as; µ e = 2.46 (cm2/Vs) and µ h = 0.0540 (cm2/Vs), respectively. Thus, results of these calculation prove that our theoretical studies provide a deep insights to confirm that investigated donor compounds would be appropriate vs PDIs acceptors for OSCs. [ABSTRACT FROM AUTHOR]

Highlights • A novel dual-axis optoelectronic level that simultaneously detects the dual-axis inclined angles is proposed. • The optoelectronic level employs viscous liquid as the reference to gravity. • The auto-collimation structure, using the liquid surface reflection, is designed to detect the level angle. • The compensation structure is designed to prevent the angular drift of the emitted laser. Abstract This paper presents a novel dual-axis optoelectronic level that can simultaneously measure the dual-axis inclined angles. Viscous liquid is employed as the reference to gravity. Whether the level is horizontal or not, the liquid surface keeps horizontal under the influence of gravity. The single-mode fiber-coupled laser provides the stable illumination beam as the light source, which is divided into two beams after passing through the splitter. One of the beams is transformed into the level angle by the auto-collimation structure, using the liquid surface. And the other beam is processed by the compensation structure, which can prevent the angular drift of the emitted laser. The experiment results revealed that the designed level worked well. Its angle error was less than ±2 arcsec in the range of ±1000 arcsec and less than ±0.3 arcsec in the range of ±100 arcsec. The peak to peak resolution of the final data was about 0.1 arcsec and the response time was less than 3 s. Furthermore, the drift of the level was about 0.1 arcsec in 1 h, which showed good stability in long-term. [ABSTRACT FROM AUTHOR]

Herein, we report photoluminescence properties by embedding a purely organic fluorophore into a polymer matrix. Biopolymer-polylactic acid [PLA] doped with bischalcone, [1, 3-bis (4-bromobenzylidene) cyclohexan-2-one] is found to show exciting properties for applications in optoelectronics. This paper focuses on the preparation thin films with different dopant concentrations 2%, 4%, 6%, 8% (w/v) dispersed in PLA by solvent casting method. They are characterized by IR, SEM, TGA, DSC and Powder XRD; evidenced the formation matrix-dopant composite films. The UV absorbance of the pristine PLA film is observed at λ max 300 nm and for the doped films at λ max 330 nm. It is observed that as the dopant concentration increased, the intensity of absorbance also increased indicating the UV blocking property of the films with doped bischalcone. The prominent photoluminescence (PL) emission peak at 440 nm is obtained for doped PLA with dopant dependent increase in absolute quantum yield of 41–62%. Thus, the composite material obtained by doping the bischalcone into the polymer matrix is found to block UV radiations and emit light in the visible region, which could make these films versatile materials for optical applications. • Preparation of bischalcone doped PLA thin films by solvent casting method. • Characterization of the films by spectral and morphological studies. • UV abs and PL of the film show proportionate increase with the dopant concentration. • The material might find applications in optoelectronics. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Hierarchical synthesis of urchin-like V 2 O 5 hollow spheres were prepared. • The plausible growth mechanism of urchin-like V 2 O 5 hollow spheres were proposed. • The responsivity and specific detectivity were 1.109 AW−1, 1.525 × 1011 Jones, respectively. Abstract In this paper, we synthesized hierarchical urchin-like V 2 O 5 hollow spheres by simple, low cost and one-pot hydrothermal method without using any kind of templates and surfactants. The X-ray diffraction analysis indicated the urchin-like V 2 O 5 hollow spheres exhibited orthorhombic crystal structure. The field emission scanning electron microscope and high-resolution transmission electron microscope demonstrate that the morphology is urchin-like hollow spheres with an average diameter is about (3–4 μm). Time-dependent experiments were performed to investigate the plausible mechanism for the formation of hierarchical urchin-like V 2 O 5 hollow spheres through Ostwald ripening. And then, these urchin-like hollow spheres were used to fabricate the photodetector for the high-performance key parameters. The critical parameters such as photosensitivity, responsivity and specific detectivity were calculated 2.79 × 102, 1.109 AW−1, 1.525 × 1011 Jones, respectively, under 41.3 mWcm-2 of 450 nm laser at an applied bias of −5 V. The urchin-like V 2 O 5 hollow spheres show excellent photodetection properties upon illumination, because of the cumulative effect of the primary building blocks of nanorods and proper hollow structure that enhance the resultant excellent device performance. Overall, this photodetector offers extraordinary potential and pave the way for an effective approach to fabricate next-generation optoelectronic and electronic devices. [ABSTRACT FROM AUTHOR]

Abstract Functionalized photochromic materials have attracted a growing interest during the last few decades since they are promising materials to be used in optoelectronics and photonics. In this paper, the results of the nonlinear optical (NLO) investigation (second and third harmonic generation) of spin deposited high-quality thin films of styrylquinoline containing methacrylic polymers studied by using Maker fringes technique employing 30 ps laser pulses at fundamental wavelength of 1064 nm are presented. Photochromic styrylquinoline units were oriented in the thin films by corona poling technique promoting second order NLO activity. Strong dependence of the NLO response upon the structure of the polymers has been found, which is related to the different charge transfer within the styrylquinoline fragments. These investigations were completed by theoretical studies using HOMO-LUMO energy levels theory and the first and second order hyperpolarizability values. Good compatibility has been achieved between the theoretical and experimental results. Studied styrylquinoline-based polymers showed the contrast in NLO response after their trans-cis photoisomerization making them interesting for using in photonic devices. Graphical abstract Image 1057 Highlights • Control of NLO response upon the molecular structure of the styrylquinoline fragments. • Strong charge transfer lead to strong NLO modulation of NLO properties. • High electron delocalization induce large NLO properties. • Trans -cis photoisomerization lead to photoswitchable NLO properties due to UV irradiation. [ABSTRACT FROM AUTHOR]

Abstract Transparent conducting oxide (TCO) films with high mobility and low carrier density exhibit both high conductivity and high transparency in the visible and near-infrared regions. TCO films that can be fabricated at low process temperatures provide opportunities to improve the performance of solar cells and to develop new optoelectronic applications. This paper describes the current status of ZnO- and In 2 O 3 -based TCO layers and their application in Cu(In,Ga)Se 2 mini-modules. The use of solid-phase crystallized In 2 O 3 :W,H layers instead of conventional ZnO:Al or ZnO:B layers increases both short-circuit current density and fill factor, and a high certified conversion efficiency of 20.93% has been achieved via this approach. Highlights • Current progress with high mobility transparent conducting oxide films is described. • ZnO- and In 2 O 3 -based films are applied in Cu(In,Ga)Se 2 mini-modules. • The low process temperatures (<160 °C) of the films improve solar cell performance. • Compared with ZnO:Al or ZnO:B, spc -In 2 O 3 :W,H increases the short-circuit density. • A high certified conversion efficiency of 20.93% is achieved with spc -In 2 O 3 :W,H. [ABSTRACT FROM AUTHOR]

Abstract The conductivity of a monolayer graphene at intraband transitions is sensitive on the Fermi level and on the wavelength of the incident beam. Changing conductivity values through these parameters thus may offer better control of light impinging on graphene. In this paper, we investigate reflection, the simplest interaction of light on such surface, by looking at the Goos-Hänchen (GH) shift experienced by the incident light where the wavelength is at terahertz range. With this wavelength range, we assume that the carriers in graphene undergo intraband transition. We calculate that spatial and angular GH shifts can be present. For both GH shifts in general, we find that increasing the Fermi level changes the incident angle at which the maximum GH shifts arise. Moreover, we see that at higher frequencies, the amount of beam shift decreases with the Fermi level. At lower frequencies on the other hand, the shift becomes proportional to the Fermi level. Upon obtaining the measurable shifts, we find that the magnitude of the physical shifts can be easily detected given appropriate experimental parameters. Our results may increase the utility of graphene in optoelectronics devices and applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel SU-8 mesh chip was fabricated for high-throughput 3D wound healing assay. • "Wound on a chip" model was constructed for wound healing assay by real-time monitoring the cells growth processes. • This 3D cell culture method provided more complex cellular processes and some tissue-specific properties. Abstract The dynamic process of cells is the basis of many biological problems in living organisms and has been a major research subject over several decades. In this paper, we present a novel SU-8 mesh chip (SMC) with thousands of chamber arrays for high-throughput 3D wound healing assay, which could directly and efficiently evaluate 3D cell growth process and cellular drug responses in vitro. Four kinds of adherent cells (HeLa, HepG2, HUVEC, NIH-3T3) were successfully seeded into the SMC to form three-dimensional hollow cell aggregates models with precisely pre-defined sizes and shapes, followed by monitored their spontaneous growth process in real time. Compared with traditional 2D wound healing assay, this 3D model provided more complex cellular processes and some tissue-specific properties, which conferred a high degree of clinical and biological relevance to in vitro models. NIH-3T3 and HUVEC cell aggregates in this chip that termed as "wound on a chip" model had been developed and further investigated the drug response in these 3D wound healing processes by applying different concentrations of candidate drugs. [ABSTRACT FROM AUTHOR]

Abstract The development of new fluorescent dyes has been a continuously interesting topic due to their wide applications in various optoelectronic, analytical and biological fields. In this paper, a novel xanthene dye CzR has been developed by hybridizing of the carbazole and rhodamine skeletons in one molecular. To regulate the optical properties of CzR , its N -methyl derivative MeCzR was prepared by the reaction of CzR with iodomethane. The absorption and emission properties of CzR and MeCzR were investigated in detail. Because the distribution positions of the positive charge within the chromophore are environment-dependent, the optical properties of the dye CzR are strongly pH-dependent. However, the optical properties of MeCzR are stable in water in a wide range of pH. To demonstrate the application of this novel dye, we synthesized the novel Cu2+-selective fluorescent probe MeCzR-Cu. The probe exhibited a specific ability to recognize the Cu2+ ion over other chemically close ions and with a detection limit down to the nanomolar range. Meanwhile, the probe MeCzR-Cu is living cell membrane permeable and can be utilized as a practical vehicle for detecting Cu2+ in complex cellular systems. Graphical abstract Image 1 Highlights • A novel xanthene dye CzR and its N -methyl derivative MeCzR have been developed. • The absorption and emission properties of CzR and MeCzR were investigated in detail. • A novel Cu2+-selective fluorescent probe MeCzR-Cu has been prepared from MeCzR. • The probe MeCzR-Cu can be utilized as a practical vehicle for detecting Cu2+ imaging. [ABSTRACT FROM AUTHOR]

Abstract: An all-optical reconfigurable logic operation essentially constitutes a key technology for avoiding complex and speed limited optoelectronics conversions and performing various processing tasks. All-optical reconfigurable logic operations with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed and described. The paper describes the all-optical reconfigurable logic operations using a set of all-optical multiplexer and optical switches. We have tried to exploit the advantages of TOAD-based switch to design an integrated all-optical circuit which can perform the different logic operations AND, XOR, NOR and NOT. Numerical simulation confirming described methods is given in this paper. [Copyright &y& Elsevier]

Abstract This paper reports the synthesis of 5-(5-methyl-benzofuran-3-ylmethyl)-3H- [1, 3, 4] oxadiazole-2-thione (5MBOT) and characterization by FT-IR, FT-Raman, 1H NMR, 13C NMR and UV spectral studies. The density functional theory (DFT) calculations have been executed for the 5MBOT using B3LYP/6-31++G (d, p) basis set. The fundamental modes of the vibrations were designated by the potential energy distribution (PED), and the computed and experimental values support each other. The 1H NMR and 13C NMR chemical shifts of 5MBOT were estimated by gauge-including atomic orbitals (GIAO) method and compared with the experimental chemical shifts. The UV–Vis method used to study the visible absorption maxima (λ max ) by using Time-Dependent DFT. Further, the Mulliken population analysis (MPA), natural population analysis (NPA) charges, thermodynamic properties at different temperatures were presented. The calculated HOMO and LUMO energies show that charge transfer within the molecule. The natural bonds orbital (NBO) also computed. Optoelectronic properties have been carried out by combination of DFT calculations and molecular dynamics (MD) simulations, in order to assess the potential of this structure for applications in organic electronics. Further, the study encompassed calculations of reorganization energies for holes and electrons and charge transfer rates. DFT calculations have been also used in order to identify locations possibly sensitive towards the autoxidation mechanism, which correlates between bond dissociation energy for hydrogen abstraction and the mechanism. The MD simulations have been used to understand interaction of 5MBOT with water molecules. Molecular docking studies reveals the antifungal activity of 5MBOT may be due to hydrogen bonding and hydrophobic interactions with different antifungal proteins. Graphical Abstract Unlabelled Image Highlights • 5MBOT was prepared and characterized by FT-IR, FT-Raman, 1HNMR, 13CNMR and UV spectral studies. • DFT calculations, optoelectronic properties and molecular dynamics simulations have been studied. • Experimental and theoretical spectral analyses were matched well. • The title molecule exhibited good chemical stability and hardness. • Intramolecular interactions were estimated by NBO analysis. • Molecular docking analysis show anti-microbial activity due to hydrogen bonding and hydrophobic interactions with proteins. [ABSTRACT FROM AUTHOR]

Abstract CdS nanoparticles have attracted much attention due to their important properties. To investigate their structural and optoelectronic properties and CdS-ligand interactions, we compare theoretical calculations and experimental results. In this paper, we determine the structures, vibrational frequencies, and electronic properties of CdS nanoparticles with the DFT method in the B3LYP/LANL2DZ. Considering the addition influence of solvent and ligand, our calculated IR, Raman and absorption spectra can be coherent with the defined experimental results. Subsequently, the absorption spectra of (Cd 3 S 3) m structures are calculated using the TD-DFT method. Furthermore, we use HRTEM technic to verify our calculations. We obtain a good agreement. Through conformation and structure analysis of S Cd-SR, we find that ligands are attached to the nanoparticle only via S Cd bond. Moreover, we also attest that the absorption peaks of all structures are transition from d to p orbitals, and the gaps energy decreases in the order of the m value. Graphical abstract We explore the effect of ligand on Cd 3 S 3 structure. Through conformation and structure analysis of Cd 3 S 3 -ligand, we find that ligand take an essential role in the structure of nanoparticles. The two ligands, MPA and TG, have a similar influence because the main effect comes from thiol. Image Highlights • DFT calculations and spectroscopic (IR, Raman and UV–visible) investigations of CdS clusters – ligands interactions. • Influence of ligands and solvent on the structures of CdS clusters. • Impact of quantum size effect on the variation of gap energy. • Experimental FTIR, HRTEM spectra of CdS-ligand confirmed with DFT calculations. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The paper presents an original technique for quantitative analysis of the chemical composition from photoelectron lines obtained by X-ray photoelectron spectroscopy. Despite the simplicity, a proposed algorithm of spectral fit refinement allows one to control the fitting accuracy and to minimize the errors in determining the concentrations of chemical compounds. An obvious advantage of the iterative approach is the automatic convergence to the true spectrum fit form under correct input assumptions and conditions. The validity of the refinement technique is proved by the results of its application in the study of the chemical composition of three types of solid-state structures of nanoelectronics and spintronics. The error decrease in determining the concentration provides revealing new physicochemical features of the phase formation under various methods and parameters of the creation of structures. The discovered dependences of magnetic, electrical and optoelectronic properties on the local composition of nanosystems make it possible to formulate scientifically grounded principles of their development. Due to its simplicity and versatility, the spectral fit refinement technique can be extended to other experimental methods, where mathematical processing of spectral data is required. [ABSTRACT FROM AUTHOR]