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We combine biodegradable plastic (polyvinyl alcohol/glycerol polymer), and cellulose-based tissue paper in a very short time (5 s) by a facile way to form a new matrix, named plastic-paper, which has high optical transmittance (~ 89%) and high optical haze (~ 90%) in broadband. Results showed that the plastic-paper is durable in different solvents, with high folding strength (over 3500 folding times) and good mechanical strength (> 30 MPa tensile strength). Interestingly, the plastic-paper presents a two-sidedness of surface morphology. The smooth side shows high light transmittance and the rough side presents high optical haze. The smooth side of the plastic-paper is successfully applied to Organic Light-Emitting Diode (OLED). When the rough surface of plastic-paper is used in solar cells, the maximum output power increases by 2.6% compared with bare solar cells. The developed plastic-paper with high optical transmittance and high optical haze holds a great potential in flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

Summary: Paper substrate has many advantages, such as low cost, bendable, foldable, printable, and environmentally friendly recycling. Nowadays, paper has been further extended as a flexible platform to deliver electronic information with the integration of organic optoelectronic devices, such as organic thin-film transistor, organic solar cell, organic electrochromic device, and organic light-emitting device. It has great potential to become the new generation of flexible substrate. Given rough surface and porous of paper, many efforts have been underway in recent years to enable the compatibility between optoelectronics and paper substrate. In this review, we present the development history of paper and its physicochemical properties, and summarize the current development of paper-based organic optoelectronic devices. We also discuss the challenges that need to be addressed before practical uses of paper-based organic optoelectronic devices.

Despite the ever‐increasing demand for transparent power sources in wireless optoelectronics, most of them have still relied on synthetic chemicals, thus limiting their versatile applications. Here, a class of transparent nanocellulose paper microsupercapacitors (TNP‐MSCs) as a beyond‐synthetic‐material strategy is demonstrated. Onto semi‐interpenetrating polymer network‐structured, thiol‐modified transparent nanocellulose paper, a thin layer of silver nanowire and a conducting polymer (chosen as a pseudocapacitive electrode material) are consecutively introduced through microscale‐patterned masks (which are fabricated by electrohydrodynamic jet printing) to produce a transparent conductive electrode (TNP‐TCE) with planar interdigitated structure. This TNP‐TCE, in combination with solid‐state gel electrolytes, enables on‐demand (in‐series/in‐parallel) cell configurations in a single body of TNP‐MSC. Driven by this structural uniqueness and scalable microfabrication, the TNP‐MSC exhibits improvements in optical transparency (T = 85%), areal capacitance (0.24 mF cm−2), controllable voltage (7.2 V per cell), and mechanical flexibility (origami airplane), which exceed those of previously reported transparent MSCs based on synthetic chemicals. [ABSTRACT FROM AUTHOR]

Transparent paper with high transmission haze has garnered great attention due to its potential applications in light management of optoelectronics as a bulk optical material. Herein, we investigated the transmission haze and mechanical properties of transparent paper with different fiber species. The morphological dimensions of cellulose fibers (Northwood, Eucalyptus wood, Manila hemp) before and after 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) treatment were investigated in detail. The effect of fiber morphology and preparation methods on transmission haze and mechanical properties (tensile strength, Young’s modulus, bursting strength) of the resultant paper was then analyzed. The results showed that transparent paper with TEMPO-treated northern fibers possessed highest optical transmittance and transmission haze, as well as strongest mechanical strength compared to two other transparent paper. Furthermore, transparent paper prepared by solution casting exhibited higher mechanical strength, but lower transmission haze compared to paper prepared by vacuum filtration. It’s worth noting that sub-micro and nanofiber partially contributed to the transparency and mechanical properties of the resulting transparent paper. This work sheds light on the preparation of highly transparent and strong paper with excellent light scattering behavior for manipulating light behavior of optoelectronics as a bulk optical material. [ABSTRACT FROM AUTHOR]

Flexible photodetectors functionalized by transition metal dichalcogenides have attracted great attention due to their excellent photo-harvesting efficiency. However, the field of optoelectronics still requires advancement in the production of large-area, broad band and flexible photodetectors. Here we report a flexible, stable, broad band and fast photodetector based on a MoS2/WSe2 heterostructure on ordinary photocopy paper with pencil-drawn graphite electrodes. Ultrathin MoS2/WSe2 nanohybrids have been synthesized by an ultrahigh yield liquid-phase exfoliation technique. The thin sheets of WSe2, and MoS2 contain two to four layers with a highly c-oriented crystalline structure. Subsequently, the photodetector was exploited under ultra-broad spectral range from 400 to 780 nm. The photodetector exhibits excellent figure of merit such as on/off ratio of the order of 103, photoresponsivity of 124 mA W−1 and external quantum efficiency of 23.1%. Encouragingly, rise/decay time of about 0.1/0.3 s was realized, which is better than in previous reports on paper-based devices. [ABSTRACT FROM AUTHOR]

In this concept, we showcase the upsurge in the studies of dynamic ultralong room‐temperature phosphorescence (RTP) materials containing inorganic and/or organic components as versatile photo‐responsive platforms. The goal is to provide a comprehensive analysis of photo‐controllable RTP, and meanwhile delve into the underlying RTP properties of various classes of photochromic materials including metal‐organic complexes, organic‐inorganic co‐crystals, purely organic small molecules and organic polymers. In particular, the design principles governing the integration of the photochromic and RTP moieties within a single material system, and the tuning of dynamic RTP in response to light are emphasized. As such, this concept sheds light on the challenges and opportunities of using these tunable RTP materials for potential applications in optoelectronics, particularly highlighting their use of reversible information encryption, erasable light printing and rewritable smart paper. [ABSTRACT FROM AUTHOR]

Self-powered flexible photodetectors which can efficiently and sustainably operate without the need for external electric input are important in today's era for portable and optoelectronics devices. Paper-based photodetectors integrate advantages, like high flexibility, bio-degradability, large photosensitive area, and low fabrication cost. Herein, we have developed large area, broadband, and highly stable photodetectors based on Graphite/ZnO–WS2 nanohybrid on paper. Encouragingly, Graphite/ZnO–WS2 nanohybrids show self-powered photodetection with a high responsivity of 7.1 × 10–2 mA/W in the visible spectral range to 9.8 mA/W in NIR spectral range. Also, the photodetector exhibited excellent photoresponsivity of 1.80 A/W, detectivity of 1.5 × 1012 Jones, and EQE of 207% under the illumination at 1080 nm with a light intensity of 50 µW/cm2 at 0.2 V bias. Due to excellent binding between the paper and detector active materials as well as the high flexibility of the paper, the device shows greater flexibility and stability up to 1000 bending cycles. Moreover, the photodetector exhibits high stability in humid and ambient environments. [ABSTRACT FROM AUTHOR]

Abstract: Paper, one of the oldest materials for storage and exchange of human's information, has been reinvented as a building component of electronic and optoelectronic devices over the past decades with successful demonstration of paper‐based or paper‐using devices. These recent achievements can meet the demand for lightweight, cost‐effective, and/or flexible electronic and optoelectronic devices with advanced functionality and reduced manufacturing costs. This article provides a review of electronic and optoelectronic devices relying on or making use of the unique properties achievable with paper‐based materials. Basic scientific/technical principles, quantitative comparisons of material, electronic and/or optical properties, and benefits for each paper‐based application are given. Application‐specific research challenges, future design considerations, and development directions are also discussed. [ABSTRACT FROM AUTHOR]

Purpose -- New types of substrates were used for fabrication of printed electroluminescent structures. Polymer foils mainly used as substrates for such optoelectronic elements were replaced with paper and textiles. Printing on non-transparent substrate requires elaboration of printed transparent electrode, while usually polyester foils with sputtered ITO transparent electrodes are used. The paper aims to discuss these issues. Design/methodology/approach -- Electroluminescent structures were fabricated with elaborated polymer compositions filled with nanomaterials, such as carbon nanotubes and graphene platelets, dielectric and luminophore nanopowders. Structures were printed as "reverse stack", where transparent electrode is printed on top of the last luminophore layer. For that carbon nanotubes and graphene platelets filled composition was used, deposited with spray-coating technique. Findings -- Main issue with new substrates is proper wetting with the use of screen-printing pastes, and much higher roughness especially for textiles. Originality/value -- Fully functional structures were obtained, but several disadvantages were observed that needs to be eliminated in further studies. [ABSTRACT FROM AUTHOR]

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]

The low yield of indium tin oxide (ITO) thin-film deposition is an important factor in optoelectronic semiconductor production. An effective reclamation process was developed that uses ultrasonic electroetching and a designed bulge-form tool to remove the defective ITO nanostructure from the optical polyethyleneterephthalate (PET) surfaces of digital paper. In the current experiment, the assistance of ultrasonics was found to be more effective than pulsed current, requiring no increase in electric power. The large length of the bulge-form tool's cathode, with a small gap width between the cathode and the workpiece, requires less time to do the same amount of ITO etching. The small end radius of the cathode, combined with enough electric power, results in very fast etching. Additionally, electric power, when combined with a fast feed rate, provides highly effective etching. A higher rate of removal of the defective ITO nanostructure corresponds to high temperature, a large electrolyte flow rate, or a high rotational speed of the electrodes. Importantly, ultrasonic electroetching with the designed bulge-form tool requires only a short period of time to remove the ITO's thin-film coatings easily and cleanly. [ABSTRACT FROM AUTHOR]

Free-standing optoelectronic graphene-CdS-graphene oxide (G-CdS-GO) composite papers were prepared by vacuum-assisted self-assembly. G-CdS hybrids were first prepared by a hydrothermal method and GO acts as a dispersant which makes it easier to disperse them to form relatively stable aqueous suspensions for fabricating paper. Transmission electron microscopy shows that CdS quantum dots (QDs) with an average size of approximately 1-2 nm were distributed uniformly on the graphene sheets. Photoluminescence measurements for the as-prepared G-CdS-GO composite paper showed that the surface defect related emissions of attached CdS QDs decrease and blue shift obviously due to the change in particle size and the interaction of the surface of the CdS QDs with both the GO and the graphene sheets. The resulting paper holds great potential for applications in thin film solar cells, sensors, diodes, and so on. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We investigated high‐performance amorphous metal‐oxide semiconductor based optoelectronics using low‐temperature and solution process technologies. In particular, metal‐oxide and quantum dots hybrid phototransistors exhibited ultra‐high photodetectivity up to 4×1017Jones in a broad range of detection wavelength from ultraviolet to infrared ranges. In addition, we employed artificial visual perception circuit based on metal‐oxide synaptic transistors with metal chalcogenide semiconductors for optoelectronic neuromorphic devices. We also demonstrated large‐scaled ultra‐flexible and stretchable device showing promising next‐generation wearable optoelectronics. [ABSTRACT FROM AUTHOR]

The traditional base station in C-RAN is divided into three parts: a pool of centralized baseband units (BBUs), a fronthaul network that links the BBUs and remote radio units (RRUs), and RRUs. This paper proposes a novel cooperative algorithm for resource optimization in a time-wavelength division multiplexed (TWDM) passive optical network (PON) incorporating a cloud radio access network (C-RAN). First, a joint collaborative strategy is deployed to optimize cooperative caching and transmission in the wireless and optical domains. Then, the quality of experience (QoE) is improved by bandwidth configuration and caching. Simulation results show that the average throughput of the proposed QoE-aware video cooperative caching and transmission mechanism (QACCTM) algorithm is approximately 30% higher than that of other algorithms. Compared with the relative average residual clutter power (RARCP) and quality-aware wireless edge caching (QAWEC) algorithms, the proposed QACCTM algorithm reduces the access delay by approximately 27.1% and 15.9%, respectively. [ABSTRACT FROM AUTHOR]

Inkjet printing (IJP) has evolved over the past 30 years into a reliable, versatile, and cost‐effective industrial production technology in many areas from graphics to printed electronic applications. Intensive research efforts have led to the successful development of functional electronic inks to realize printed circuit boards, sensors, lighting, actuators, energy storage, and power generation devices. Recently, a promising solution‐processable material class has entered the stage: metal halide perovskites (MHPs). Within just 10 years of research, the efficiency of perovskite solar cells (PSCs) on a laboratory scale increased to over 25%. Despite the complex nature of MHPs, significant progress has also been made in controlling film formation in terms of ink development, substrate wetting behavior, and crystallization processes of inkjet‐printed MHPs. This results in highly efficient inkjet‐printed PSCs with a power conversion efficiency (PCE) of almost 21%, paving the way for cost‐effective and highly efficient thin‐film solar cell technology. In addition, the excellent optoelectronic properties of inkjet‐printed MHPs achieve remarkable results in photodetectors, X‐ray detectors, and illumination applications. Herein, a comprehensive overview of the state‐of‐the‐art and recent advances in the production of inkjet‐printed MHPs for highly efficient and innovative optoelectronic devices is provided. [ABSTRACT FROM AUTHOR]

With the continuous development of flexible electronics, multi-functional device integration, artificial intelligence technology, etc., flexible wearable sensors are playing an increasingly important role in people's daily motion monitoring. However, current flexible wearable sensors have problems such as low accuracy, poor real-time performance, and poor stability in motion monitoring, which seriously hinder the better application of flexible wearable sensors and are not conducive to the collection and monitoring of motion signals. To this end, this paper designed a flexible wearable sensor motion monitoring system and tested its performance through the preparation and performance research of new functional polymer conjugated materials. The research results show that the motion monitoring system designed based on the new functional polymer conjugated material flexible wearable sensor has good monitoring accuracy and real-time performance. When the output data is 500 pieces, the running monitoring accuracy reaches 95.4%, and the monitoring feedback time is 0.321 s; the high jump movement monitoring accuracy rate reaches 97%, and the monitoring feedback time is 0.287 s; the long jump movement monitoring accuracy rate reaches 96%, and the monitoring feedback time is 0.296 s. This shows that the flexible wearable sensor motion monitoring system of this paper has better performance and can meet the current demand for accuracy and realtime motion monitoring. This study highlights the impact of new functional polymer conjugated materials on flexible wearable sensors, helping to further solve the deficiencies of flexible wearable sensors in sports monitoring and promote their better development. [ABSTRACT FROM AUTHOR]

An introduction to the special issue of "IET Optoelectronics," based on papers from Semiconductor and Integrated Optoelectronics (SIOE) 2017, is presented.

In this paper, the crystal structure, optical and electronic properties of two related rubidium iodide halide perovskites RbSiI3 and RbGeI3 are investigated and discussed thoroughly. The calculations of these properties are performed using the generalized gradient approximation under Perdew–Burke–Ernzerhof functional (GGA–PBE). Also, the structural optimizations and accurate optoelectronic properties have been achieved by exploiting full-potential linearized augmented plane wave method (FP-LAPW). Analysis of optimization results exposed that the volume per unit cell and lattice parameter (a0 = 5.8348 Å (RbSiI3)) and (a0 = 5.9631 Å (RbGeI3)) are closely in agreement with the previous results. In addition, the calculated values of tolerance factor (TF ≈ 1.0) satisfy the creation criterion for perovskites, and the negative and small values of formation energy (ΔFE) confirm the chemical stability of studied compounds. The results of density of states and band structures reveal that RbSiI3 and RbGeI3 are nonmagnetic semiconductors having a proper direct energy gap (Eg) of 0.465 and 0.953 eV, respectively, along the M–M symmetry directions in the first Brillouin zone. The 2-D distributions of charge density confirm that the chemical bonding of Rb–I and Si/Ge–I bonds obey the covalent and ionic nature. Moreover, we have calculated and discussed the optoelectronic properties, real ε1(ω) and imaginary ε2(ω) functions, optical absorption α(ω), reflectivity R(ω) and refractivity n(ω). The results obtained in this study like structural stability, suitable Eg and highly accurate optical absorption α(ω) of visible light waves, indicate the possible exploitation of semiconductors RbSiI3 and RbGeI3 and make them candidate materials for optoelectronics, such as photovoltaic solar cells, photosensors, photodetectors and photodiodes devices. [ABSTRACT FROM AUTHOR]

Phase-pure crystalline cubic boron nitride (c-BN) thin films are of immense scientific and technical interest because of their suitable properties for optoelectronic and high-power applications, high thermal conductivity and hardness, chemical inertness to ferrous materials in high-temperature and caustic environments, and high optical transmittance over a broad wavelength range from the ultraviolet (UV) to the visible spectrum. However, the lack of controlled fabrication techniques for high-quality c-BN films significantly affects the reliable practical applications of this material. Recently, phase-pure single-crystal c-BN and a new phase of BN with unique properties, called quenched-BN (Q-BN), have been synthesized using a pulsed laser annealing (PLA) technique to overcome the current impediments in c-BN synthesis. This review paper comprehensively examines the current status of analytical research on the growth, characterization, and properties (optical and electrical) of c-BN films fabricated by different synthesis techniques, with a particular emphasis on the immensely promising PLA technique. In particular, the paper focuses on the processes used to obtain phase-pure c-BN films via epitaxial growth, characterization of defects and interfaces, and control of the structural, electrical, and optical properties of these films by controlling the growth parameters, including the laser–solid interaction for the direct conversion of nanocrystalline hexagonal boron nitride (h-BN) into crystalline c-BN using the PLA technique. The latest developments in c-BN electronics are also discussed, with a focus on producing p-and n-type conductivity using different dopants to achieve dopant concentrations far beyond the retrograde thermodynamic solid solubility limits. Finally, the future prospects and possible applications in emerging areas are discussed, as well as the goals and guidelines for future research of PLA-grown c-BN films. A comprehensive overview of the properties, application, characterization, shortcomings, and future prospects of c-BN [ABSTRACT FROM AUTHOR]

Blue/deep-blue emission is crucial for organic optoelectronics but remains a formidable challenge in organic afterglow due to the difficulties in populating and stabilizing the high-energy triplet excited states. Here, a facile strategy to realize the efficient deep-blue organic afterglow is proposed via host molecules to sensitize the triplet exciton population of guest and water implement to suppress the non-radiative decays by matrices rigidification. A series of highly luminescent deep-blue (405–428 nm) organic afterglow materials with lifetimes up to 1.67 s and quantum yields of 46.1% are developed. With these high-performance water-responsive materials, lifetime-encrypted rewritable paper has been constructed for water-jet printing of high-resolution anti-counterfeiting patterns that can retain for a long time (>1 month) and be erased by dimethyl sulfoxide vapor in 15 min with high reversibility for many write/erase cycles. These results provide a foundation for the design of high-efficient blue/deep-blue organic afterglow and stimuli-responsive materials with remarkable applications. Though realizing organic materials with deep blue emission is attractive for next-generation display technologies, achieving this emission in afterglow molecules remains a challenge. Here, the authors report blue organic afterglow via a strategy involving guest sensitization and matrix rigidification. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, optical and transport properties of Polyvinyl Alcohol/Silver incorporated Zinc Oxide (PVA/Ag–ZnO) nanocomposites of varying Ag–ZnO nanoparticles content prepared by solution casting method are studied to explore their multifunctional applications. The nanocomposites are characterized using X-ray diffraction, Scanning electron microscope, Energy-dispersive X-ray analysis, UV–Visible spectroscopy and Fourier transform infra-red spectroscopy. The UV–visible spectra showed zero transmittance in the UV region with increasing Ag–ZnO nanoparticles content in the PVA matrix suggesting that the nanocomposites could be used as a potential UV shielding material. The optical band gap energy decreases from 5.77 to 1.54 eV with increasing Ag–ZnO nanoparticles content in the PVA matrix. Frequency- and temperature-dependent dielectric measurement of the samples reveals maximum dielectric constant at PVA/15 wt% Ag–ZnO nanocomposite. Dielectric loss results showed a lossless behaviour at higher frequencies (< 0.2), suggesting that the prepared samples are suitable for use in high-frequency applications. The AC conductivity studies reveal that electrical conduction mechanism in the nanocomposites is governed by the correlated barrier hopping mechanism. Activation energy calculation indicates the involvement of two different types of conduction mechanism in the samples. The Nyquist plot for all the samples is fitted using the equivalent circuit model. The studied results show that the PVA/Ag–ZnO nanocomposites can serve as potential candidates for optoelectronic and electronic device application. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the influence of thickness on the optoelectrical properties of poly(2‐methoxy‐5‐(2′‐ethyl‐hexoxy)‐1,4‐phenyle‐ne‐vinylene) is discussed. The main goal of our measurements was to describe the relationship between thickness of films and their optoelectrical properties. We discovered that there is always certain minimum film thickness needed for development of conformational structure and for changes in optoelectrical behavior. [ABSTRACT FROM AUTHOR]

This paper presents a test methodology to facilitate the measuring processes of LiDAR receiver ICs by avoiding the inherent walk error issue. In a typical LiDAR system, a costly laser diode driver emits narrow light pulses with fast rising edges, and the reflected pulses from targets enter an optical detector followed by an analog front-end (AFE) circuit. Then, the received signals pass through the cascaded amplifiers down to the time-to-digital converter (TDC) that can estimate the detection range. However, this relatively long signal journey leads to the significant decline of rising-edge slopes and the output pulse spreading, thus producing inherent walk errors in LiDAR receiver ICs. Compensation methods requiring complex algorithms and extra chip area have frequently been exploited to lessen the walk errors. In this paper, however, a simpler and lower-cost methodology is proposed to test LiDAR receiver ICs by employing a high-speed buffer and variable delay cells right before the TDC. With these circuits, both START and STOP pulses show very similar pulse shapes, thus effectively avoiding the walk error issue. Additionally, the time interval between two pulses is easily determined by varying the number of the delay cells. Test chips of the proposed receiver IC implemented in a 180-nm CMOS process successfully demonstrate easier and more accurate measurement results. [ABSTRACT FROM AUTHOR]

This document is a collection of featured articles in the field of optoelectronics. Optoelectronics involves the study and development of electronic devices that emit or detect light, including gamma rays, X-rays, ultraviolet, infrared radiation, and visible light. The articles cover a range of topics, including a new passive optical network system, performance evaluation of a PET scanner, the design of a high-Q perfect absorber, the evolution of bioamplifiers, optical chaos communication, threshold voltage shift in OFETs, near-infrared CMOS image sensors, interface functionalization in perovskite solar cells, and the visualization of halide segregation in perovskite materials. These articles provide valuable insights and advancements in the field of optoelectronics. [Extracted from the article]

High-performance photodetection is becoming increasingly important for the advancement of technology. Very few materials are available that can respond to light across the ultraviolet to the infrared (IR) range. These materials are very much required for optoelectronic devices. Two-dimensional (2D) layered materials became relevant following the discovery of graphene. Transition-metal chalcogenides belong to the 2D layered material class, as well. The field of optoelectronic applications makes extensive use of them. The current study investigated the photodetector device by doping pure SnS nanoflakes with Fe, Mn, Mg, Pd, and W. These materials were used to create paper-based, flexible, biodegradable electronics through a solvent-free hand-print technique. The Mg-doped SnS photodetector has the highest photo response performance among the devices. With a specific detectivity value of 1.64 × 1010 Jones and a responsivity value of 52 mA W–1, the 7% Mg-doped SnS exhibits the best response among the different Mg doping. Extensive on–off cycles were used to assess the switching stability of the device, observing clear photo response and photoswitching behavior. The photoswitching curves of the device as created and the device after 8 months show an amazing degree of consistency, indicating the device's resilience in open-air environments. The device was bent repeatedly to test its twisting, foldability, and flexibility. It continuously displayed a definite photoswitching trend. Testing in a very basic and acidic environment verified the device's chemical stability, and its photo response and photoswitching functions remain functional. When the paper-based photodetector's thermal stability was examined at various temperatures, the findings demonstrated that the device continues to function normally and produce photocurrent. Considering how quickly technology is developing nowadays and how much waste is produced by electronics, switching to paper-based gadgets could help achieve sustainability goals. [ABSTRACT FROM AUTHOR]

A novel crystal benzophenone's nonlinear optical applications are pivotal. Benzophenone is one of the promising organic nonlinear optics materials for their high energy laser photonic application. It has already been possible to generate crystals of benzophenone in various ways. In this research, the slow evaporation method at room temperature was successful in making a single crystal of benzophenone. In this paper, synthesis, growth, characterization and applications of low melting organic nonlinear optics benzophenone crystal in order to improve their structural and physical properties are reported. Different characterization methods were applied to the grown crystals. The lattice parameters of the grown material were obtained by single crystal X-ray diffraction (XRD) study. The results of the single crystal XRD analysis showed that the produced crystals are a component of an orthorhombic system with the space group P212121 and the lattice parameters are a = 7. 9 9 9 5 (9)  Å, b = 1 0. 2 8 6 5 (1 0)  Å, c = 1 2. 1 2 4 7 (1 3)  Å, α = β = γ = 9 0 ∘ and V = 9 9 7. 7 0 (1 8)  Å3. Ultraviolet-visible (UV–Vis) spectrum indicates that the crystal is transparent (72%) in the entire visible region with a cutoff wavelength of 258 nm. The transparency of the grown crystals has been confirmed using the UV–Vis spectrum. The second harmonic generation (SHG) efficiency of the grown crystal was measured using an Nd-YAG laser and it was found to be 1.8 greater than potassium dihydrogen orthophosphate (KDP). The FT-IR spectrum was examined in order to identify the many functional groups. The formation of the material was confirmed qualitatively by FT Raman spectral analyses. Mechanical properties such as Vicker's microhardness number, Yield strength, Fracture toughness, Brittleness index and Elastic stiffness constant values were determined using Vicker's microhardness test. The thermal stability of the grown crystal was studied by thermal analysis. [ABSTRACT FROM AUTHOR]

Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides often exhibit a type II band alignment, which facilitates the generation of interlayer excitons. As a bonded pair of electrons and holes in the separation layer, interlayer excitons offer the chance to investigate exciton transport due to their intrinsic out-of-plane dipole moment and extended exciton lifetime. Furthermore, interlayer excitons can potentially analyze other encoding strategies for information processing beyond the conventional utilization of spin and charge. The review provided valuable insights and recommendations for researchers studying interlayer excitonic devices within van der Waals heterostructures based on transition metal dichalcogenides. Firstly, we provide an overview of the essential attributes of transition metal dichalcogenide materials, focusing on their fundamental properties, excitonic effects, and the distinctive features exhibited by interlayer excitons in van der Waals heterostructures. Subsequently, this discourse emphasizes the recent advancements in interlayer excitonic devices founded on van der Waals heterostructures, with specific attention is given to the utilization of valley electronics for information processing, employing the valley index. In conclusion, this paper examines the potential and current challenges associated with excitonic devices. [ABSTRACT FROM AUTHOR]

A dual-sided metasurface structure, consisting of two different sets of sub-wavelength periodic metallic patterns on its two sides, can offer a promising platform for the design of multifunctional and directional insensitive devices. This paper presents an elaborative study of the structural and mathematical analyses of the frequency response of a dual-sided metasurface structure. It has been found that the ratio between resonating wavelength and the structure's thickness plays a deterministic role in achieving multi-functionality in such designs. The paper further presents an equivalent circuit model of the dual-sided metasurface structure to mathematically analyze the role of impedance in achieving directional insensitivity in such devices. The proposed structural and mathematical analysis has been validated together by designing a directional insensitive rasorber in the latter half of the paper. The analyses done in this paper can open up a broad avenue for the research and development of metasurface-based directional insensitive multifunctional optoelectronics devices. [ABSTRACT FROM AUTHOR]

This study analyzes the scientific knowledge diffusion paths of graphene for optoelectronics (GFO), where graphene offers wide applications due to its thinness, high conductivity, excellent transparency, chemical stability, robustness, and flexibility. Our investigation is based on the main path analysis which establishes the citation links among the literature data in order to trace the significant sequence of knowledge development in this emerging field. We identify the main development paths of GFO up to the year 2012, along which a series of influential papers in this field are identified. The main path graph shows that knowledge diffusion occurs in key subareas, including reduced graphene oxide, chemical vapor deposition, and exfoliation techniques, which are developed for the preparation and applications of GFO. The applications cover solar cells, laser devices, sensing devices, and LCD. In addition, the main theme of GFO research evolves in sequence from small-graphene-sample preparation, to large-scale film growth, and onto prototype device fabrication. This evolution reflects a strong industrial demand for a new transparent-conductive film technology. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue, including one on the molecular beam epitaxial (MBE) growth and spectroscopy of dilute nitride InAsN:Sb for mid-infrared applications, another on design and characteristics of staggered InGaN quantum-well light emitting diodes in the green spectral regime and another on semiconductor optoelectronics.

The paper presents the possibilities of, and methods for, acquiring, analysing and processing optical signals in order to recognise, identify and counteract threats on the contemporary battleground. The main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated, including the acquisition of optical emitter signatures, as well as ultraviolet (UV) and thermal (IR) signatures. The physical parameters and values describing the emission of laser radiation are discussed, including their importance in terms of creating optical signatures. Moreover, it has been shown that in the transformation of optical signals into signatures, only their spectral and temporal parameters can be applied. This was confirmed in experimental part of the paper, which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser rangefinders. It has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in "solar-blind" band, various events can be identified quickly and faultlessly. The same is true for IR signatures, where the amplitudes of the recorded signal for several wavelengths are compared. This was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground, namely Rocket Propelled Grenade (RPG) launches and explosions after hitting targets, trinitrotoluene (TNT) explosions, firing armour-piercing, fin-stabilised, discarding sabots (APFSDS) or high explosive (HE) projectiles. The final section describes a proposed model database of emitters, created as a result of analysing and transforming the recorded signals into optical signatures. [ABSTRACT FROM AUTHOR]

With the capacities of self-learning, acquainted capacities, high-speed looking for ideal arrangements, solid nonlinear fitting, and mapping self-assertively complex nonlinear relations, neural systems have made incredible advances and accomplished broad application over the final half-century. As one of the foremost conspicuous methods for fake insights, neural systems are growing toward high computational speed andmoo control utilization. Due to the inborn impediments of electronic gadgets, it may be troublesome for electronic-implemented neural systems to make the strides these two exhibitions encourage. Optical neural systems can combine optoelectronic procedures and neural organizationmodels to provide ways to break the bottleneck. This paper outlines optical neural networks of feedforward repetitive and spiking models to give a clearer picture of history, wildernesses, and future optical neural systems. The framework demonstrates neural systems in optic communication with the serial and parallel setup. The graphene-based laser structure for fiber optic communication is discussed. The comparison of different balance plans for photonic neural systems is made within the setting of hereditary calculation and molecule swarm optimization. In expansion, the execution comparison of routine photonic neural, time-domain with and without extending commotion is additionally expounded. The challenges and future patterns of optical neural systems on the growing scale and applications of in situ preparing nonlinear computing will hence be uncovered. [ABSTRACT FROM AUTHOR]

The use of wearable sensors for calculating gait parameters has become increasingly popular as an alternative to optoelectronic systems, currently recognized as the gold standard. The objective of the study was to evaluate the agreement between the wearable Opal system and the optoelectronic BTS SMART DX system for assessing spatiotemporal gait parameters. Fifteen subjects with progressive supranuclear palsy walked at their self-selected speed on a straight path, and six spatiotemporal parameters were compared between the two measurement systems. The agreement was carried out through paired data test, Passing Bablok regression, and Bland-Altman Analysis. The results showed a perfect agreement for speed, a very close agreement for cadence and cycle duration, while, in the other cases, Opal system either under- or over-estimated the measurement of the BTS system. Some suggestions about these misalignments are proposed in the paper, considering that Opal system is widely used in the clinical context. [ABSTRACT FROM AUTHOR]

In this paper, tri-phase Fe2O3–MgO–CuO nanocomposites (NCs) and pure CuO, Fe2O3 and MgO nanoparticles (NPs) were prepared using sol–gel technique. The physical properties of the prepared products were examined using SEM, XRD, and UV–visible. The XRD data indicated the formation of pure CuO, Fe2O3 and MgO NPs, as well as nanocomposite formation with Fe2O3 (cubic), MgO (cubic), and CuO (monoclinic). The crystallite size of all the prepared samples was calculated via Scherrer's formula. The energy bandgap of CuO, Fe2O3 and MgO and Fe2O3–MgO–CuO NCs were computed from UV–visible spectroscopy as following 2.13, 2.29, 5.43 and 2.96 eV, respectively. The results showed that Fe2O3–MgO–CuO NCs is an alternative material for a wide range of applications as optoelectronics devices due to their outstanding properties. [ABSTRACT FROM AUTHOR]

In recent years, with the further ministration of the semiconductor device in integrated circuits, power consumption and data transmission bandwidth have become insurmountable obstacles. As an integrated technology, photonic integrated circuits (PICs) have a promising potential in the post‐Moore era with more advantages in data processing, communication, and diversified sensing applications for their ultra‐high process speed and low power consumption. Silicon photonics is believed to be an encouraging solution to realize PICs because of the mature CMOS process. The past decades have witnessed a huge growth in silicon PICs. However, there is still a demand for the development of silicon PICs to enable powerful chip‐scale systems and new functionalities. In this paper, a review of the photonic components, functional blocks, and emerging applications for PICs is offered. The common photonic components are classified into several sections, including on‐chip light sources, fiber‐to‐chip couplers, photonic resonators, waveguide‐based sensors, on‐chip photodetectors, and modulators. The functional blocks of the PICs mentioned in this review are photonic memories and photonic neural networks. Finally, the paper concludes with emerging applications for further study. [ABSTRACT FROM AUTHOR]

This article presents the classification of optoelectronics encoder faults in a permanent magnet synchronous motor (PMSM) drive system. This paper proposes the deep neural networks (DNNs) speed sensor faults classification application in the vector-controlled PMSM drive. This approach to the issue has not been discussed in the literature before. This work presents a solution based on early detection with the use of the model reference adaptive system (MRAS) estimator and fault classification based on artificial intelligence. The innovative nature of this work is also due to the simulation of speed sensor damage using the developed optoelectronics encoder model in the Matlab/Simulink environment. This work is focused on simulation studies, which have been supported by experimental results obtained on the MicroLabBox platform. This article compares two structures of deep neural networks in fault detection. The results were also compared with previous experimental studies on the classification of speed sensor failures using shallow neural networks. [ABSTRACT FROM AUTHOR]

Symmetry-deficient two-dimensional (2D) layered materials induce a highly anisotropic optical response due to the anisotropy in their crystal structure, facilitating their application in polarized nanodevices. Intercalation is a new way to tune the optoelectronic properties of materials by inserting guest atoms into layered host materials, and 2D layered structures stacked with van der Waals gaps are a prerequisite for this phase of the technique. In this paper, 2D tellurium nanosheets were synthesized with a hydrothermal method, and copper atoms were inserted with a wet chemical method. The widening of the crystal plane spacing proves the introduction of copper atoms, and polarization−related second-harmonic-generation (SHG) studies reveal the intrinsic anisotropic modes of the two samples, and birefringent properties are found with polarizing light microscopy. We further investigated the electrical properties of the samples, and the embedding of the copper atoms caused the samples to exhibit higher currents, but their devices lost the gate control effect. [ABSTRACT FROM AUTHOR]

The ternary ZnIn2S4 has recently gained significant attention due to its potential applications in various optoelectronics and photocatalysis sectors. In the current study, ZnIn2S4 nanoparticles were prepared using a simple microwave-assisted synthesis method with different irradiation powers varying from 180 W--720 W. Structural analysis confirmed their polycrystalline nature with the appearance of ZnIn2S4 and In2S3 phases. The variation in diffraction pattern intensity and Raman vibrational bands with irradiation power indicates structural rearrangements induced with power variation. Morphological studies confirmed the formation of agglomerate nanoparticles with size variation as induced by different microwave powers. Broad absorption across the visible and near-infrared regions and the increased band gap enhance their photocatalytic and sensing applications. An increased irradiation power in the ZnIn2S4 lattice reduced intermediate levels within the band gap, altering the optical responsiveness. The blue shift in absorption edges with microwave power increased the optical band gap by reducing disorder and defects. The refractive indices were estimated using different theoretical models and reduced with an increase in the band gap. Thermal analysis revealed endothermic peaks. These ZnIn2S4 nanoparticles displayed an enhanced photocurrent under white light, increasing tenfold with microwave power. The greater powered ZIS (ZIS-720 W) nanomaterial showed the best photoresponse and is well suited for optoelectronic application. All of their optical and electrical properties make them suitable for various optoelectronic devices, particularly in detection applications. [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]

SrTiO3 is a wide bandgap cubic perovskite oxide and displays many exotic properties, i.e., transparent conductivity, photocatalysis, metallicity, ferroelectricity, superconductivity, colossal magnetoresistance, two-dimensional electron gas, etc., due to the manipulations of defect chemistry and constituent elements via impurity doping. This paper reports on the intricacy of the structural and optoelectronic properties of the epitaxially stabilized 5 at. % Ta-doped SrTiO3 (001) thin films on LaAlO3 (001) substrates by systematically varying the growth temperature and oxygen partial pressure during the pulsed laser deposition process. The influences of Ta dopant and growth parameters on the epitaxial quality of these layers are understood by determining the dopant location and its concentration in the SrTiO3 lattice. The complex relationships of optical and electronic properties on growth parameters, dopant concentration, and single crystal quality of the films are demonstrated. The observed low resistivity (∼5 × 10−3 Ω cm) and high optical transparency (∼85%–90%) of optimized Ta-doped SrTiO3 films offer it as an exciting material for next generation transparent optoelectronics. [ABSTRACT FROM AUTHOR]

Photonic Integrated Circuits (PICs) on indium phosphide have matured significantly over the past couple of decades and have found use in many system applications. Some PIC efforts on other group III-V substrates have also been initiated. In numerous cases, the usefulness of these PICs is because of the reduction in size, weight, and power they provide, but in many cases also because of the higher performance made possible by the improved relative phase stability among optical paths as well as the reduction of inter-element coupling losses. In this paper, as part of this special issue in tribute to Prof. Daniel Dapkus, we focus on monolithic PICs that provide a system function, especially those that incorporate and build on widely-tunable laser technology as a key element. Some of the early widely-tunable laser work is reviewed, and a selection of past system-on-a-chip developments is presented as background. Then, more recent system-on-a-chip advances performed by the author’s groups are reviewed in more detail. Key advances are highlighted. [ABSTRACT FROM AUTHOR]

Structural health monitoring of aircraft assures safety, integrity and reduces cost-related concerns by reducing the number of times maintenance is required. Under aerodynamic loading, aircraft is subjected to strain, in turn causing damage and breakdown. This paper presents a review of experimental works, which focuses on monitoring strain of various parts of aircraft using optical fibre sensors. In addition, this paper presents a discussion and review on different types of optical fibre sensors used for structural health monitoring (SHM) of aircraft. However, the focus of this paper is on fibre bragg gratings (FBGs) for strain monitoring. Here, FBGs are discussed in detail because they have proved to be most viable and assuring technology in this field. In most cases of strain monitoring, load conditioning and management employs finite element method (FEM). However, more effort is still required in finding the accurate positions in real time where the sensors can be placed in the structure and responds under complex deformation. [ABSTRACT FROM AUTHOR]

Transparent conductors (TCs) are materials, which are characterized by high transmission of light and simultaneously very high electrical DC conductivity. These materials play a crucial role, and made possible numerous applications in the fields of electro-optics, plasmonics, biosensing, medicine, and “green energy”. Modern applications, for example in the field of touchscreen and flexible displays, require that TCs are also mechanically strong and flexible. TC can be broadly classified into two categories:uniformandnon-uniformTC. The uniform TC can be viewed as conventional metals (or electron plasmas) with plasma frequency located in the infrared frequency range (e.g. transparent conducting oxides), or ultra-thin metals with large plasma frequency (e.g. graphen). The physics of the nonuniform TC is much more complex, and could involve transmission enhancement due to refraction (including plasmonic), and exotic effects of electron transport, including percolation and fractal effects. This review ties the TC performance to the underlying physical phenomena. We begin with the theoretical basis for studying the various phenomena encountered in TC. Next, we consider the uniform TC, and discuss first the conventional conducting oxides (such as indium tin oxide), reviewing advantages and limitations of these classic uniform electron plasmas. Next, we discuss the potential of single- and multiple-layer graphene as uniform TC. In the part of the paper dealing with non-uniform metallic films, we begin with the review of random metallic networks. The transparency of these networks could be enhanced beyond the classical shading limit by the plasmonic refractive effects. The electrical conduction strongly depends on the network type, and we review first networks made of individual metallic nanowires, where conductivity depends on the inter-wire contact, and the percolation effects. Next, we review the uniform metallic film networks, which are free of the percolation effects and contact problems. In applications that require high-quality electric contact of a TC to an active substrate (such as LED or solar cells), the network performance can be optimized by employing a quasi-fractal structure of the network. We also consider the periodic metallic networks, where active plasmonic refraction leads to the phenomenon of the extraordinary optical transmission. We review the relevant literature on this topic, and demonstrate networks, which take advantage of this strategy (the bio-inspired leaf venation (LV) network, hybrid networks, etc.). Finally, we review “smart” TCs, with an added functionality, such as light interference, metamaterial effects, built-in semiconductors, and their junctions. [ABSTRACT FROM PUBLISHER]

In this paper, the performance of Cu-(In,Ga)-S2 (CIGS2) solar cells with adjusting composite [Cu]/([Ga] + [In]) (CGI)-ratio absorber was explored and compared through an improved three-stage co-evaporation technique. For co-evaporating CIGS2 absorber as a less toxic alternative to Cd-containing film, we analyzed the effect of the CGI-ratio stoichiometry and crystallinity, and explored its opto-electric sensing characteristic of individual solar cell. The results of this research signified the potential of high-performance CIGS2-absorption solar cells for photovoltaic (PV)-module industrial applications. For the optimal CIGS2-absorption film (CGI = 0.95), the Raman main-phase signal (A1) falls at 291 cm−1, which was excited by the 532 nm line of Ar+-laser. Using photo-luminescence (PL) spectroscopy, the corresponding main-peak bandgaps measured was 1.59 eV at the same CGI-ratio film. Meanwhile, the best conversion efficiency (η = 3.212%) and the average external quantum efficiency (EQE = 51.1% in the visible-wavelength region) of photo-electric properties were achieved for the developed CIGS2-solar cells (CGI = 0.95). The discoveries of this CIGS2-absorption PV research provided a new scientific understanding of solar cells. Moreover, this research undeniably contributes to a major advancement towards practical PV-module applications and can help more to build an eco-friendly community. [ABSTRACT FROM AUTHOR]