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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]

The progressive downscaling of silicon‐based microelectronic devices delivers compact and advanced integrated circuits for fast data processing and computing. Similarly, the miniaturization of conventional optoelectronics is also an important frontier of technology for emerging lighting, imaging, communication, and sensing. Herein, this study reports a miniature dual‐functional diode (DF‐diode) with both light‐emitting and light‐detecting functionalities. The proposed micro‐scale DF‐diode exhibits a record high responsivity of 300 mA W−1 at 265 nm with an ultrafast response rise time of 3.7 ns in light‐detecting mode. While operating in emitting mode, it demonstrates an extraordinarily high −3 dB optical bandwidth above 585 MHz with an enhanced external quantum efficiency performance. Significantly, the development of micro‐scale DF‐diodes has opened up a new avenue toward the realization of an effective and long‐distance solar‐blind optical communication system in the future. [ABSTRACT FROM AUTHOR]

Layered van der Waals (vdW) dichalcogenides are distinguished by their unique crystal structures and high structural tunability, rendering them suitable for applications in optics and optoelectronics. Despite significant processes, some fundamental questions remain in two-dimensional (2D) vdW dichalcogenides, such as clarifying detailed structure–property relationship and further improving the optoelectronic performance. Herein, by applying pressure to tune the crystal structure in 2D vdW dichalcogenide SiTe2, we realized a five orders of magnitude boost in photocurrent at 8 GPa. Such an enhancement is attributed to bandgap narrowing and an increased carrier concentration. Furthermore, bandgap closing and metallization were observed at 15.4 GPa, further suggesting the significant change of electronic structure upon compression. This study not only elucidates the intriguing pressure-induced behavior of SiTe2 but also paves the way for harnessing the unique pressure-responsive properties of 2D vdW dichalcogenides in advanced optoelectronic systems. [ABSTRACT FROM AUTHOR]

A new group of halides AgXF3 (X = Cr, Zr) compounds having perovskite structures were studied via the first principle approach supported on DFT, coded within WEIN2K and their properties were extensively investigated. Both AgCrF3 and AgZrF3 materials were confirmed to have the stability in the cubic structures because of having the Gold-Schmidt tolerance factor values in the range of stability. The band-gap information of all these materials were gathered by using the method of the modified Becke-Johnson potential. The metallic nature was found for the studied materials. The material AgCrF3 showed the greater tendency to restrain both the alteration in shape as well as in volume. Both AgXF3 and AgXF3 materials the showed nature of ductility, which was confirmed from both the Poisson's ratio and Pugh's ratio calculations and also the ionic nature of bonding was detected for all the studied materials. Moreover, the high optical reflectivity for both compounds are found. The obtained metallic nature and high optical reflectivity make them appropriate for electrode material and reflective coating. [ABSTRACT FROM AUTHOR]

The use of semiconductors based on abundant and less expensive materials in photovoltaic industry has grown since electricity consumption has increased, alloys such as Cu2ZnSn(S1-xSex)4 have recently attracted attention, due to its structural, optical and electronic properties which make it a very promising candidate as an absorber layer in photovoltaic applications. The lattice mismatch of Cu2ZnSn(S1-xSex)4 with Cu2NiGeS4 as substrate for solar cell architecture reveals that low Se content (0.1≤x≤0.4) is favorable, and thus, by reducing Se content from 40 to 10% induces a decrease in optical parameters such as refractive index from 5.475 to 3.834 for near-infrared wavelengths, and both extinction and absorption coefficients are from 0.478 to 0.211 and from 7.956×104 to 6.912×104 cm-1, respectively, for almost along the visible spectrum. Additionally, the bandgap energy of Cu2ZnSn(S1-xSex)4 in kesterite structure increases from 1.267 to 1.442 eV at room temperature, while the compressive strain of the epitaxial layer reduces from 3.93 to 2.39% and from 4.62 to 3.17% on the growth plane and following the direction of growth, respectively. [ABSTRACT FROM AUTHOR]

Herein, structural, optoelectronic, and thermoelectric characteristics of Ba2CaTeO6 and Ba2CaWO6 oxides double perovskite have been evaluated by first-principles calculations. Enthalpy of formation and tolerance factor are computed to ensure the respective structural and thermodynamical stability. Ba2CaTeO6 and Ba2CaWO6 have mBJ computed bandgaps of 5.87 eV and 4.20 eV, respectively. Furthermore, the optical parameters like dielectric constants (ԑ1(ω) & ԑ2(ω)) and other related parameters are computed. The thermoelectric (TE) parameters were examined using the BoltzTraP package. The ZT values of Ba2Ca(Te/W)O6 at 450 K are 0.76/0.79, respectively. The outcomes of the Ba2CaTeO6 and Ba2CaWO6 double perovskite show that these materials are potential contenders for UVbased optical and various TE gadgets. [ABSTRACT FROM AUTHOR]

With the advent of two‐dimensional (2D) van der Waals (vdW) materials, many non‐van der Waals (nvdW) materials have been synthesized and are being exploited for novel applications. Bismuth oxychalcogenides (Bi2O2X; X is S, Se, Te), a nvdW series with moderate band gap semiconductors, possess high carrier mobility and air stability. The layers in Bi2O2X stay with a formal bond, giving rise to distinct structural, optical, thermal, and electronic properties different from conventional vdW materials. Herein, these properties, their synthesis, and transfer methods of 2D Bi2O2X are examined. The photodetector application of Bi2O2X and their heterostructure (HS) is surveyed with special attention to Bi2O2Se. Beyond the photodetector, the other emerging application fields, such as gas‐bio sensors, optoelectronic imaging, integrated memory, solar cells, and photothermal technology of Bi2O2X are looked over. Based on the ongoing research and challenges, the strategies for future innovations are presented from basics to miniaturized applications. In view of the band offsets of vdW and nvdW semiconductors, the type of HS of a series of 94 vdW‐nvdW sets is proposed. This review will guide future studies on Bi2O2X and their HS to meet the increasing demands in multifunctional applications from the laboratory to the industrial scale. [ABSTRACT FROM AUTHOR]

[Display omitted] Printed optoelectronics are paramount in emerging research due to their cost-effectiveness, flexibility, and compatibility with diverse substrates, offering innovative solutions for efficient light manipulation and energy conversion. The pursuit of printed optoelectronics is driven by its potential to overcome challenges in traditional optoelectronics, fostering advancements in areas such as wearable devices, the Internet of Things (IoT), and renewable energy technologies. Two-dimensional transition metal dichalcogenides (2D-TMDs) are promising for emerging research in printed optoelectronics because of their unique optical, electrical, and mechanical properties. By harnessing the exceptional properties of 2D-TMDs, such as high surface area, excellent charge carrier mobility, and tunable bandgaps, in printed optoelectronics, researchers unlock cost-effective and flexible avenues for efficient light manipulation, making these materials pivotal for advancing the field and addressing current optoelectronic challenges. The synthesis of 2D-TMD inks and their integration into printed devices offer a promising paradigm shift, enticing explosive interest with the potential for enhanced performance, scalability, and diverse applications in the dynamic landscape of printed optoelectronics. However, the prominent research advances in terms of optoelectronics, light-matter solid interactions, and printable optoelectronic inks based on 2D TMD materials have not been systematically reviewed. This review focuses on synthesizing and optimizing 2D-TMD inks, exploring their varied applications in printed optoelectronic devices, and paving the way for transformative advancements in this field. This review summarizes the latest research developments in this rapidly evolving area and emphasizes the crucial role of 2D-TMD inks in advancing printed optoelectronics, exploring their unique properties and potential for novel device architectures. The comprehensive outlook in this review proposes a roadmap for ongoing and future research endeavors in the ever-evolving field of printed optoelectronics. [ABSTRACT FROM AUTHOR]

In recent years, there has been a surge in twistronics research, uncovering diverse emergent properties in twisted two-dimensional (2D) layered materials. Vertically stacking these materials with slight azimuthal deviation or lattice mismatch creates moiré superlattices, optimizing the structure and energy band and leading to numerous quantum phenomena with applications in electronics, optoelectronics, photonics, and twistronics. Recently, the superior (opto)electronic properties of these moiré superlattices have shown potential in catalysis, providing a platform to manipulate catalytic activity by adjusting twist angles. Despite their potential to revolutionize 2D catalysts, their application in catalysis is limited to simple reactions, and the mechanisms behind their catalytic performance remain unclear. Therefore, a comprehensive perspective on recent studies is needed to understand their catalytic effects for future research. [ABSTRACT FROM AUTHOR]

Organophosphorus heterocycles have long been acknowledged for their significant potential across diverse fields, including catalysis, material science, and drug development. Incorporating phosphorus functionalities into organic compounds offers a means to effectively tailor their medicinal properties, augment biological responses, and enhance selectivity and bioavailability. The distinctive physical and photoelectric characteristics of phosphorus‐containing conjugated compounds have garnered considerable interest as promising materials for organic optoelectronics. These compounds find extensive utility in various applications such as light‐emitting diodes, photovoltaic cells, phosphole‐based fluorophores, and semiconductors. [ABSTRACT FROM AUTHOR]

Silver (Ag), not only alters the electrical and optical properties of ZnO thin films but also has the ability to enhance its ultraviolet (UV) emission. However, the mechanism for the UV emission enhancement has not been clearly understood. The study focused on optimization of the optical properties of pristine and Ag-doped ZnO films through variation of preparation and post deposition parameters. The prepared pristine and Ag-doped ZnO films were found to be polycrystalline in nature with diffraction peaks corresponding to ZnO and Ag phases. Increase in Ag and annealing temperature led to increase in the transmittance of Ag-doped ZnO films. The refractive index was found to increase with a decrease in substrate-source distance, an increase in Ag concentration, film thickness, and annealing temperature. The extinction coefficient for the analysed films was found to decrease with increase in substrate-source distance and annealing temperature, but increased with increase in film thickness. An inherent dissipation of electromagnetic energy in pristine and Ag-doped ZnO films was observed due to strong interaction between low and wide optical band gap energies of Ag and ZnO, respectively. The optical band gap energy increased with an increase in substrate-source distance, decreased with an increase in film thickness and annealing temperature at a wavelength, λ = 650 nm . The observed trends have been explained based on polarizability, reduced structural defects, thermal expansion, and lattice vibrations in pristine and Ag-doped ZnO films. The obtained optimized properties show that Ag-doped ZnO films are good candidates for optoelectronic applications. [ABSTRACT FROM AUTHOR]

This work aims to enhance the optical and structure characteristics of silicon nitride (Si3N4)/silica (SiO2)/poly-methyl methacrylate (PMMA). The films of (PMMA–SiO2–Si3N4) were fabricated using casting method. The structure and optical characteristics of Si3N4/SiO2/PMMA nanostructures were studied, the structure characteristics of PMMA/SiO2/Si3N4 nanostructures included: FTIR and optical microscope. The optical properties were investigated at wavelength (λ = 240–740 nm). The results confirmed the absorption increased of 61.5% and transmission reduced of 42.2% when the Si3N4 and SiO2 NPs content reached 6.9 wt%, these results make them as a superior materials for many optical fields. The energy gap of PMMA reduced from 4.25 to 3.09 eV when the Si3N4 and SiO2 NPs content reached 6.9 wt%, this behavior made the Si3N4/SiO2/PMMA nanostructures suitable for optoelectronics nanodevices. The optical constants, the absorption coefficient, refractive index, extinction coefficient, real and imaginary dielectric constants, as well as optical conductivity increases with increasing in the concentrations of Si3N4 and SiO2 NPs. The results confirmed that the PMMA/SiO2/Si3N4 nanomaterials can be considered as future nanosystems to exploit in a variety of promising nanoelectronics and optics applications. [ABSTRACT FROM AUTHOR]

Praseodymium doped lanthanum arsenate, denoted as La 1-x Pr x AsO 4 , has been synthesized with different concentrations of the dopant (x = 0.5 %; 1 %; 2 %; 3 % and 5 %) via the combustion method and their optoelectronic properties have been investigated. A study of the crystalline structure and size of the compound by XRD confirms that both the pristine LaAsO 4 and Pr-doped LaAsO 4 are pure and maintain a monoclinic crystal structure, with the crystalline size ranging from 60 to 76 nm. The morphological study of the nanoparticles by SEM analysis reveals that all samples, regardless of the concentration of Pr3+, consist of homogeneously packed and irregularly shaped small particles. The optical studies by absorption and fluorescence spectroscopies highlight the unique optoelectronic characteristics of La 1-x Pr x AsO 4 , with absorption predominantly in the UV and blue regions and prominent emission peaks in the visible spectrum, most notably at 610 nm. The optimal luminescence is observed at a 0.5 % Pr3+ doping level, deviating from typical trends as higher concentrations lead to diminished emission intensity and lifetime due to concentration quenching effects. The application of Density Functional Theory (DFT) with GGA + PBE and GGA + PBE + U approximations has effectively elucidated the electronic structure and optical properties of the Pr-doped LaAsO 4. The incorporation of Pr's 4f states within the LaAsO 4 forbidden band significantly alters the material's electronic landscape, notably reducing the optical band gap from 4.45 eV to 2.299 eV. This modification in the band structure aligns favourably with the dielectric function curves and density of states analyses, corroborating the observed visible light emission in the doped samples. [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]

Layered van der Waals (vdW) dichalcogenides are distinguished by their unique crystal structures and high structural tunability, rendering them suitable for applications in optics and optoelectronics. Despite significant processes, some fundamental questions remain in two-dimensional (2D) vdW dichalcogenides, such as clarifying detailed structure–property relationship and further improving the optoelectronic performance. Herein, by applying pressure to tune the crystal structure in 2D vdW dichalcogenide SiTe2, we realized a five orders of magnitude boost in photocurrent at 8 GPa. Such an enhancement is attributed to bandgap narrowing and an increased carrier concentration. Furthermore, bandgap closing and metallization were observed at 15.4 GPa, further suggesting the significant change of electronic structure upon compression. This study not only elucidates the intriguing pressure-induced behavior of SiTe2 but also paves the way for harnessing the unique pressure-responsive properties of 2D vdW dichalcogenides in advanced optoelectronic systems. [ABSTRACT FROM AUTHOR]

The Janus MoSSe and alloy MoSxSe(1-x), belonging to the family of two-dimensional (2D) transition metal dichalcogenides (TMDs), have gained significant attention for their potential applications in nanotechnology. The unique asymmetric structure of Janus MoSSe provides intriguing possibilities for tailored applications. The alloy MoSxSe(1-x) offers a tunable composition, allowing for the fine-tuning of the properties to meet specific requirements. These materials exhibit remarkable mechanical, electrical, and optical properties, including a tunable band gap, high absorption coefficient, and photoconductivity. The vibrational and magnetic properties also make it a promising candidate for nanoscale sensing and magnetic storage applications. Properties of these materials can be precisely controlled through different approaches such as size-dependent properties, phase engineering, doping, alloying, defect and vacancy engineering, intercalation, morphology, and heterojunction or hybridisation. Various synthesis methods for 2D Janus MoSSe and alloy MoSxSe(1-x) are discussed, including hydro/solvothermal, chemical vapour transport, chemical vapour deposition, physical vapour depositio, and other approaches. The review also presents the latest advancements in Janus and alloy MoSSe-based applications, such as chemical and gas sensors, surface-enhanced Raman spectroscopy, field emission, and energy storage. Moreover, the review highlights the challenges and future directions in the research of these materials, including the need for improved synthesis methods, understanding of their stability, and exploration of new applications. Despite the early stages of research, both the MoSSe-based materials have shown significant potential in various fields, and this review provides valuable insights for researchers and engineers interested in exploring its potential. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have attracted interest for optoelectronic applications due to their unique electronic and optoelectronic properties. In particular, multiwall (MW) CNTs film acts as perfect photo‐collector surface with the possibility to tune the absorbance by controlling the film thickness. In this work, we demonstrate two types of hybrid Si‐MWCNTs photodetectors. The MWCNTs are solution‐processed and deposited on n‐silicon substrate covered by two different dielectrics (Si3N4 or SiO2). The MWCNTs/SiO2/n‐Si device is used here as reference, since the SiO2/Si system is the most widely investigated structure in microelectronics. The electrical and optical characteristics of the reference device are compared with the corresponding of our basic MWCNTs/Si3N4/n‐Si device. The MWCNTs are deposited on the substrate with the drop casting technique. Optical performance of the SiO2 device is comparable to the Si3N4 device thus revealing a quite interesting response under UV illumination. The Si3N4 device exhibited a peak equivalent quantum efficiency (EQE) of 57% at 3 μW of source illumination power, thus demonstrating a superior performance as compared to the SiO2 device (EQE of up to 55%, which is also promising for future applications). This performance can be attributed to the great absorption in UV region of CNTs layer. Apart from this technological goal, we also investigated how MWCNTs/Si3N4 or MWCNTs/SiO2 heterojunctions perform using standard electrical characterization techniques and how the presence of the CNTs change the dielectric characteristics of both substrates. [ABSTRACT FROM AUTHOR]

The family of 2D chalcogenide semiconductors has been growing rapidly. Metal monochalcogenides, for instance, can enable new possibilities in functional electronics and optoelectronics. A Gallium Selenide (GaSe) thin flake is used to fabricate a back gated field effect transistor (FET) with n‐type conduction behavior and wide hysteresis at the ambient conditions. The device shows high mobility up to 28 cm2 V−1 s−1 with Ion/Ioff ratio over 103. Under the laser exposure, the device shows a decrease in the threshold voltage and a left‐shift of the transfer characteristic with a slight increase in the current. The transfer characteristic exhibits a hysteretic behavior with hysteresis width linearly dependent on the applied gate voltage. Moreover, the GaSe‐based FET shows a photo response with a photoresponsivity of 475 mAW−1 and detectivity of 4.6 × 1012 Jones. The photocurrent rise and decay times are 0.1 and 1.3 s, respectively. Furthermore, the GaSe FET device can be used as a performant memory device with well separated states and memory window enhanced by the laser exposure, confirming an optoelectronic memory class. [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]

It is crucial to develop advanced optoelectronic devices that incorporate multiple functions, including sensing, storage, and computing, which is considered at the forefront of semiconductor optoelectronics to meet emerging functional diversification. In this study, by stacking the n‐type Ga2O3 with the n‐type MoS2 flakes, a Ga2O3/MoS2 heterostructure optoelectronic device with high rectification ratio of ≈105 and on/off ratio of ≈108 is fabricated, which achieves high detectivity of 1.34 × 109 Jones and high responsivity of 28.92 mA/W. More importantly, the Ga2O3/MoS2 heterostructure device shows potential ability to integrate sensing and memorizing, simultaneously, which can be used as artificial neuromorphic synaptic. The device exhibits excellent photo‐induced synaptic functions including short‐term plasticity, long‐term plasticity, and paired‐pulse facilitation, realizing the ability to couple light and electrical signals by Pavlovian associative learning. At last, the device also demonstrates the information processing ability to act as optoelectronic logic gate AND by synergistically regulating the light on/off states and gate voltage. The research introduces an innovative strategy for the development of next‐generation optoelectronic devices which are highly integrated with sensing, memory, and logic processing functions, demonstrating great application prospects in constructing an efficient artificial neuromorphic visual and logic systems. [ABSTRACT FROM AUTHOR]

The development of advanced neural modulation techniques is crucial to neuroscience research and neuroengineering applications. Recently, optical-based, nongenetic modulation approaches have been actively investigated to remotely interrogate the nervous system with high precision. Here, we show that a thin-film, silicon (Si)-based diode device is capable to bidirectionally regulate in vitro and in vivo neural activities upon adjusted illumination. When exposed to high-power and short-pulsed light, the Si diode generates photothermal effects, evoking neuron depolarization and enhancing intracellular calcium dynamics. Conversely, low-power and long-pulsed light on the Si diode hyperpolarizes neurons and reduces calcium activities. Furthermore, the Si diode film mounted on the brain of living mice can activate or suppress cortical activities under varied irradiation conditions. The presented material and device strategies reveal an innovated optoelectronic interface for precise neural modulations. [ABSTRACT FROM AUTHOR]

The novel ternary 2D material Bi2O2Se exhibits numerous unique properties in the optical discipline due to its distinctive structure, rendering it of significant research importance and application potential in the domains of new‐generation microelectronics, optoelectronic sensors, and multidimensional optical recognition. However, the optical anisotropy and multidimensional angular resolution of Bi2O2Se have yet to be investigated under the condition of 3D spatial variation of incidence angle. Herein, the spatial optical sensing of the few‐layer Bi2O2Se is investigated under 3D spatially varying incidence conditions using a combination of polarized Raman spectroscopy and multidimensional angle‐resolved spectroscopy. By manipulating the incident angle conditions and adjusting the sample placement angle, a comprehensive optical characterization of materials from diverse spatial orientations is conducted. It is observed that few‐layer Bi2O2Se exhibits a systematically transformed multidimensional spatial photoresponse within visible and near‐infrared wavelengths. This demonstrates the capability of Bi2O2Se as photosensitive semiconductors for 3D stereo optical detection. Furthermore, finite difference time domain simulations reveal that the spatial optical anisotropy of few‐layer Bi2O2Se can be manifested under 3D variable‐angle incidence conditions. The work serves as a crucial guide for the future of Bi2O2Se in anisotropic integrated optics applications, based on polarization‐based chiral recognition. [ABSTRACT FROM AUTHOR]

One hindrance in transparent electronics is the lack of high‐performance p‐type transparent conductors (TCs). The state‐of‐the‐art p‐type TC, CuI, has a conductivity two orders of magnitude lower than n‐type TCs like ITO. While doping strategies have shown promise in enhancing the hole carrier density in CuI, they often come at the expense of hole mobility. Therefore, understanding how extrinsic dopants affect the mobility of CuI is critical to further improve the performance of CuI‐based TCs. Here the structural and electronic properties of Cs‐doped CuI are investigated. It is demonstrated that ≈4 at.% Cs doping in CuI increases the carrier density from 2.1 × 1019 to 3.8 × 1020 cm−3 while preserving the film microstructure and local coordination of Cu, as confirmed by HRTEM and XAS analysis. Introducing S as a co‐dopant in Cs:CuI boosts the carrier density to 8.2 × 1020 cm−3, reaching a stable conductivity of ≈450 S cm−1. In all cases, the enhanced carrier density negatively affects the hole mobility with ionized impurity scattering and increased Seebeck hole effective mass as mobility limiting mechanisms. Nonetheless, the new Cs, S co‐doped CuI exhibits high p‐type conductivity, Vis–NIR transparency, and stability, presenting an attractive candidate for future transparent electronic devices. [ABSTRACT FROM AUTHOR]

In this era of demanding invulnerable security systems against the threat of hacking, physically unclonable functions (PUFs), especially in which can spawn multiple security keys within a single device, has gained attention. This investigation explores the multi‐key generable PUF devices employing organic small molecules, specifically C8‐BTBT and PTCDI‐C13. The variation stems from the formation of irregular PN junctions, haphazardly configured grain boundaries of C8‐BTBT. A comprehensive analysis including scanning electron microscopy (SEM), atomic force microscopy (AFM), kelvin probe force microscopy (KPFM), impedance spectroscopy (IS), and optical simulation, has been substantiated the underlying mechanisms. Exploiting the photo‐responsive characteristics within the light wavelength spectrum of 660 and 530 nm, alongside the electrical characteristics, the capability to generate a total of 30 distinct multi‐security keys in a single device is been successfully. These keys, distinguished by variable parameters such as voltage, light wavelength, and the calculated photo‐to‐dark current ratio (PDCR), manifest novel quantitative and qualitative dimensions in security protocol customization. Inter‐Hamming distance and entropy of these cryptographic keys exhibit commendable averages of 51.9–53.1%, and 0.81, respectively. Moreover, a noteworthy average bit‐aliasing mean value of 51.9%, derived from four distinct batches, underscores the pragmatic feasibility of the proposed conceptual framework for PUF devices. [ABSTRACT FROM AUTHOR]

The precise mechanism governing the reversible semiconductor‐to‐metal transition (SMT) in V2O5 remains elusive, yet its investigation is of paramount importance due to the remarkable potential of V2O5 as a versatile "smart" material in advancing optoelectronics, plasmonics, and photonics. In this study, distinctive experimental insights into the SMT occurring in amorphous V2O5 through the application of highly sensitive, temperature‐dependent, in situ analyses on a V2O5 thin film deposited on soda‐lime glass are presented. The ellipsometry measurements reveal that the complete SMT occurs at ≈340 °C. Remarkably, the refractive index and extinction coefficients exhibit reversible characteristics across visible and near‐infrared wavelengths, underscoring the switch‐like behavior inherent to V2O5. The findings obtained from ellipsometry are substantiated by calorimetry and in situ secondary ion mass spectrometry analyses. In situ electron microscopy observations unveil a separation of oxidation states within V2O5 at 320 °C, despite the thin film retaining its amorphous state. The comprehensive experimental investigations effectively demonstrate that alterations in electronic state can trigger the SMT in amorphous V2O5. It is revealed for the first time that the SMT in V2O5 is solely contingent upon electronic state changes, independent of structural transitions, and importantly, it is a reversible transformation within the amorphous state itself. [ABSTRACT FROM AUTHOR]

Recently, 2D violet phosphorus (VP), a new kind of allotrope of phosphorus has attained significant attention owing to its remarkable electronic, optical, and magnetic characteristics. Tunable, large direct bandgap, high charge carrier mobility, and large optical absorption make it a potential candidate for realizing photoelectronic applications. VP demonstrates unique electronic structure, chemical stability, strong light‐matter interaction, and thermal stability that can be utilized for assembling intelligent photoelectronic devices. This review article provides comprehensive investigations of the latest synthesis techniques employed to develop the VP including its structural characterizations, stability, and degradation mechanisms. Furthermore, this review demonstrates the diverse applications of VP in optoelectronics, including photodetectors, polarization detection, imaging systems, neuromorphic optoelectronic devices, and many others. Finally, challenges and future research directions associated with the VP in terms of optoelectronics are discussed. Overall, as presented, the review offers an extensive study of VP, covering its synthesis, structural insights mechanisms, and applications in optoelectronics with the aim of stimulating further research and development in this growing field. [ABSTRACT FROM AUTHOR]

The barium strontium orthosilicate [BaSr(1-x)SiO4:xSm3+] phosphors for various concentrations have been successfully prepared by using combustion synthesis approach. The synthesized samples have been characterized by using various techniques such as X-ray diffraction (XRD), photoluminescence spectroscopy, UV–Vis spectroscopy, high-resolutions tunneling electron microscopy (HRTEM) and scanning electron microscopy (SEM). By comparing the patterns obtained from XRD of the samples with the data from the JCPDS no. 00-154-0392 that was available, orthorhombic phase formation was verified. The images obtained by scanning electron microscopy (SEM) showed the porous nature of the phosphor. The HRTEM analysis confirmed the size of the particle of the nanophosphor. When the material is excited at a wavelength of 404 nm, the photoluminescence spectra of BaSrSiO4:Sm3+ demonstrate the presence of four distinct emission peaks, which may be attributed to the transitions from the 4G5/2 energy level to the 6HJ energy levels (where J takes on the values of 5/2, 7/2, 9/2 and 11/2). The hypothesis proposed by Dexter demonstrates that the phenomenon of concentration quenching between the Sm3+-Sm3+ ions present in the phosphors arises from the dipole–quadrupole interaction between them. Its deep reddish–orange emission is shown by the estimated Commission Internationale de I'Elcairage color coordinates, indicating its applicability in display enhancement and other optoelectronic applications. This study presents a comprehensive analysis of the luminescence characteristics of the synthesized phosphors, providing a full account of these features for the first time. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS2) is a promising material with excellent electrical, magnetic, optical, and mechanical properties. It is regarded as a key candidate for the development of optoelectronic devices due to its high carrier mobility, high absorption coefficient, large exciton binding energy, polarized light emission, high surface-to-volume ratio, and tunable band gap. These properties contribute to its excellent photoluminescence and high anisotropy. These characteristics render WS2 an advantageous material for applications in light-emitting devices, memristors, and numerous other devices. This article primarily reviews the most recent advancements in the field of optoelectronic devices based on two-dimensional (2D) nano-WS2. A variety of advanced devices have been considered, including light-emitting diodes (LEDs), sensors, field-effect transistors (FETs), photodetectors, field emission devices, and non-volatile memory. This review provides a guide for improving the application of 2D WS2 through improved methods, such as introducing defects and doping processes. Moreover, it is of great significance for the development of transition-metal oxides in optoelectronic applications. [ABSTRACT FROM AUTHOR]

Organic–inorganic perovskite quantum dot (PQD)–polymer composites are emerging optoelectronic materials with exceptional properties that are promising widespread application in next‐generation electronics. Advances in the utilization of these materials depend on the development of suitable fabrication techniques to create 3D architectures composed of PQD–polymer for sophisticated optoelectronics. This study introduces a straightforward and effective method for producing 3D architectures of PQD‐encapsulated high‐performance composites (PQD‐HPCs) through direct‐ink writing (DIW). This method employs an ink composed of prefabricated PQDs and hydroxypropyl cellulose (HPC) in dichloromethane (DCM). HPC, an appropriate organic‐soluble polymer, exhibits optical transparency in the highly volatile DCM and enables the formulation of a stable, room‐temperature extrudable ink. The architectures, which are printed by adjusting the halide ratios (Cl, Br, and I) for the compositions of CH3NH3PbBr1.5I1.5, CH3NH3PbBr3, and CH3NH3PbBr1.5Cl1.5, exhibit single peak photoluminescence emissions of red (639 nm), green (515 nm), and blue (467 nm). Optimizing the printing parameters of DIW enables the precise fabrication of programmed and complex PQD‐HPC 3D architectures for advanced anti‐counterfeiting and information encryption. This method has the potential to enhance the functionality of modern printed electronic devices significantly. [ABSTRACT FROM AUTHOR]

Recently, addressing various wounds, ranging from skin injuries to pressure and chronic ulcers, has necessitated a more detailed approach to wound condition monitoring aimed at enhancing the patient's quality of life. Although most available wound dressings offer protection and promote the regeneration of wound lesions, they fail to monitor wound progression. To meet this need, this study introduces a pioneering solution: a wireless, battery‐free, optoelectronic diagnostic sensor seamlessly integrated into a colorimetric, pH‐sensitive wound dressing, designed to significantly enhance patient quality of life through improved wound care. Curcumin‐polycaprolactone (C‐PCL) dressing protect the wounds, promote cell regeneration, and possess antimicrobial properties. In addition, the dressing exhibits colorimetric pH‐monitoring capabilities across different wound conditions, enabling individuals without specialized knowledge to assess the status of their wounds. The core innovation lies in the integration of a green light‐emitting diode (LED) and photodiode, which meticulously evaluates color changes from yellow to red of colorimetric dressing, enhance the precision of this user‐friendly colorimetric diagnosis strategy. The integration of wireless battery‐free systems facilitates quantitative and real‐time monitoring of wound data in patients without inconvenience. These innovations will pave the way for rapid wound status evaluation, ensuring timely interventions and optimized care for deteriorating wound conditions. [ABSTRACT FROM AUTHOR]

Herein, a 200 nm thick films of p−$\text{p} -$SnO2 are deposited onto p−$\text{p} -$Nb2O5 thin substrates (100 nm) to construct an isotype p−$\text{p} -$Nb2O5/p−$\text{p} -$SnO2 (NSO) heterojunction devices. The device is constructed using a thermal coating method in a vacuum media of low pressure reaching 10−5 mbar. NSO heterojunctions represent two amorphous/amorphous‐stacked layers that exhibit enhanced light absorption exceeding 170% and 120% in the visible and infrared regions of light spectrum, respectively. In addition, the interface under study displays band conduction offset of 0.60–0.90 eV and valence bad offset of 0.53–0.83 eV, respectively. The NSO device, which is treated as a planner microwaves resonators by contacting it with two Ohmic Pt electrodes, shows AC electrical conduction by the correlated barrier hopping within correlated barriers of average heights of 0.127 eV. Electrical conduction is actualized within scattering time constant of 0.27 ns. NSO microwaves resonators display gigahertz cutoff frequency spectra that suit 6G technology applications. The cutoff limit can be engineered in the range of 1.0–12.0 GHz by altering the driving frequency value. The features of the NSO heterojunctions nominate them for use in optoelectronic, which require high light absorption. The heterojunction devices are also promising for potential use in microwave technology a 6G bands filters. [ABSTRACT FROM AUTHOR]

The facile in situ synthesis of graphene-coated metal-oxide nanoparticles and their potential applications in optoelectronic devices are highly anticipated. In this study, we prepared three-dimensional graphene flakes decorated with ZnO nanoparticles (LIG/ZnO) using femtosecond laser-induced zinc salt-containing cork. The LIG/ZnO heterojunction was formed by carbonizing the cork and decomposing the zinc salt in situ to coat LIG during laser irradiation. The correlation between the zinc salt concentration and the morphology, structure, and field-emission characteristics of LIG/ZnO was systematically investigated. The optimized LIG/ZnO-5 emitters demonstrate a decreased threshold electric field (E th) of 1.07 V/μm, an enhanced field enhancement factor (β) value of 20,559, and a maximum current density of 18.07 mA/cm2 at 1.96 V/μm, representing the most superior performance reported to date. The enhanced field-emission performance of LIG/ZnO can be attributed to the larger number of effective emission sites from ZnO nanoparticles and LIG edges, as well as to the energy band variation induced by the heterostructures. Density functional theory (DFT) calculations show the migration of electrons from the LIG to the ZnO after the formation of the heterojunction, which elevates the Fermi level of emitters. In addition, the accumulation of electrons on the surface of ZnO nanoparticles in the presence of a strong electric field results in a downward shift of the energy band, thereby enhancing the likelihood of electron-vacuum tunneling. • LIG/ZnO heterojunctions were prepared by ultrafast laser direct writing. • The morphology of LIG/ZnO synthesized by laser irradiation and the density of coated ZnO nanoparticles are controllable. • The relationship between the concentration of zinc salt, and field emission characteristics of LIG/ZnO was systematically studied. • The optimized LIG/ZnO-5 emitters have a low E th ∼1.07 V/μm and stable electron emission properties. [ABSTRACT FROM AUTHOR]

Flexible and miniaturized photodetectors, offering a fast response across the ultraviolet (UV) to millimeter (MM) wave spectrum, are crucial for applications like healthcare monitoring and wearable optoelectronics. Despite their potential, developing such photodetectors faces challenges due to the lack of suitable materials and operational mechanisms. Here, the study proposes a flexible photodetector composed of a monolayer graphene connected by two distinct metal electrodes. Through the photothermoelectric effect, these asymmetric electrodes induce electron flow within the graphene channel upon electromagnetic wave illumination, resulting in a compact device with ultra‐broadband and rapid photoresponse. The devices, with footprints ranging from 3 × 20 µm2 to 50 × 20 µm2, operate across a spectrum from 325 nm (UV) to 1.19 mm (MM) wave. They demonstrate a responsivity (RV) of up to 396.4 ± 5.1 mV W−1, a noise‐equivalent power (NEP) of 8.6 ± 0.1 nW Hz−0.5, and a response time as small as 0.8 ± 0.1 ms. This device facilitates direct imaging of shielded objects and material differentiation under simulated human body‐wearing conditions. The straightforward device architecture, aligned with its ultra‐broadband operational frequency range, is anticipated to hold significant implications for the development of miniaturized, wearable, and portable photodetectors. [ABSTRACT FROM AUTHOR]

Lattice deformation via substrate‐driven mechanical straining of 2D materials can profoundly modulate their bandgap by altering the electronic band structure. However, such bandgap modulation is typically short‐lived and weak due to substrate slippage, which restores lattice symmetry and limits strain transfer. Here, it is shown that a non‐volatile thermomechanical strain induced during hot‐press synthesis results in giant modulation of the inherent bandgap in quasi‐2D tellurium nanoflakes (TeNFs). By leveraging the thermal expansion coefficient (TEC) mismatch and maintaining a pressure‐enforced non‐slip condition between TeNFs and the substrate, a non‐volatile and anisotropic compressive strain is attained with ε = −4.01% along zigzag lattice orientation and average biaxial strain of −3.46%. This results in a massive permanent bandgap modulation of 2.3 eV at a rate S (ΔEg) of up to 815 meV/% (TeNF/ITO), exceeding the highest reported values by 200%. Furthermore, TeNFs display long‐term strain retention and exhibit robust band‐to‐band blue photoemission featuring an intrinsic quantum efficiency of 80%. The results show that non‐volatile thermomechanical straining is an efficient substrate‐based bandgap modulation technique scalable to other 2D semiconductors and van der Waals materials for on‐demand nano‐optoelectronic properties. [ABSTRACT FROM AUTHOR]

The design and development of organic solid-state luminescent materials stand as crucial pillars within the realm of contemporary photofunctional materials. Overcoming challenges such as concentration quenching and achieving tailored luminescent properties necessitates a judicious approach to molecular structure design and the strategic utilization of diverse stimuli to modulate molecular packing patterns. Among the myriad candidates, α-cyanodiarylethenes (CAEs) emerge with distinctive solid-state luminescent attributes, capable of forming self-assembled packing structures with varying degrees of π–π stacking. This characteristic endows them with potential in the field of intelligent molecular responsive materials and optoelectronic devices. This tutorial review embarks on an exploration of design strategies geared towards attaining tunable solid-state emission through customized packing of CAEs. It explores the utilization of stimuli responses, including such as mechanical forces, light irradiation, solvent interactions, thermal influences, as well as the utilization of co-assembly methodologies. The overarching aim of this review is to provide a widely applicable platform fostering the flourishing development of modern organic photofunctional materials through integrating principles of molecular engineering, organic optoelectronics, and materials science. [ABSTRACT FROM AUTHOR]

Since their emergence in 2014, graphitic carbon nitride quantum dots (g‐C3N4 QDs) have attracted much interest from the scientific community due to their distinctive physicochemical features, including structural, morphological, electrochemical, and optoelectronic properties. Owing to their desirable characteristics, such as non‐zero band gap, ability to be chemically functionalized or doped, possessing tunable properties, outstanding dispersibility in different media, and biocompatibility, g‐C3N4 QDs have shown promise for photocatalysis, energy devices, sensing, bioimaging, solar cells, optoelectronics, among other applications. As these fields are rapidly evolving, it is very strenuous to pinpoint the emerging challenges of the g‐C3N4 QDs development and application during the last decade, mainly due to the lack of critical reviews of the innovations in the g‐C3N4 QDs synthesis pathways and domains of application. Herein, an extensive survey is conducted on the g‐C3N4 QDs synthesis, characterization, and applications. Scenarios for the future development of g‐C3N4 QDs and their potential applications are highlighted and discussed in detail. The provided critical section suggests a myriad of opportunities for g‐C3N4 QDs, especially for their synthesis and functionalization, where a combination of eco‐friendly/single step synthesis and chemical modification may be used to prepare g‐C3N4 QDs with, for example, enhanced photoluminescence and production yields. [ABSTRACT FROM AUTHOR]

The optoelectronic and structural characteristics of the Zn1−xCrxSe (0 ≤ x ≤ 1) semiconductor are reported by employing density functional theory (DFT) within the mBJ potential. The findings revealed that the lattice constant decreases with increasing Cr concentration, although the bulk modulus exhibits the opposite trend. ZnSe is a direct bandgap material; however, a change from direct to indirect electronic bandgap has been seen with Cr presence. This transition is caused by structural alterations by Cr and defects forming, which results in novel optical features, including electronic transitions. The electronic bandgap decreases from 2.769 to 0.216 eV, allowing phonons to participate and improving optical absorption. A higher concentration of Cr boosts infrared absorption and these Cr-based ZnSe (ZnCrSe) semiconductors also cover a wider spectrum in the visible range from red to blue light. Important optical parameters such as reflectance, optical conductivity, optical bandgap, extinction coefficient, refractive index, magnetization factor, and energy loss function are discussed, providing a theoretical understanding of the diverse applications of ZnCrSe semiconductors in photonic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Halide perovskites offer a transformative potential for optoelectronics through tailoring the light‐matter interactions at the nanoscale. However, their susceptibility to environmental factors and limited compatibility with standard lithography techniques present significant challenges in precise nanopatterning. This work unveils a nature‐inspired breath figures (BFs) approach to pattern halide perovskites and enhancing their optoelectronic performance. The fabrication of BFs based on BiI3 allows for changes in nanopore size (ranging from 247 to 423 nm) and their distribution. Subsequently, these BiI3 BFs are transformed into hybrid halide MA3Bi2I9 BFs using a vapor‐assisted technique while retaining the nanoporous topology of the BiI3 structure. The resultant MA3Bi2I9 BFs show significantly enhanced light absorption compared to conventional thin films, attributed to the increased extinction and lower refractive index. The optoelectronic performance of the MA3Bi2I9 BFs is showcased by constructing a photodetector, which exhibits three orders of magnitude higher responsivity and detectivity, up to 1 AW−1 and 1.3 × 1012 Jones, respectively, outperforming the photodetectors based on solution‐processed A3B2I9 halide perovskite thin films. The BFs method provides flexibility in tuning nanoscale morphology, showcasing its potential in advancing lead‐free optoelectronics and paving the way for next‐generation optoelectronic devices. [ABSTRACT FROM AUTHOR]

The multimode optoelectronic operation in a single component device is an attractive design strategy for future optoelectronics, which demands unique and complex multifunction. Here, a novel dual‐mode optoelectronic device with both memory and switching functionalities by utilizing alternating metallic stripe domain regime‐induced controllable hysteresis of two dimensional (2D)‐crystalline VO2 films is reported. It is found that the formation and disappearance of tensile strain‐induced metallic stripe domain arrays are susceptible to temperature‐induced thermal energy, allowing controllable hysteresis in electric field‐induced metal‐insulator transition (E‐MIT) by tuning the total region of aligned metallic stripe domains within the VO2 films through current flow‐induced thermal energy. Based on the tunable hysteresis in E‐MIT, the 2D‐crystalline VO2 film‐based device exhibits successful multimode optoelectronic memory and switching operations. The device with a large hysteresis width exhibits high‐performance optoelectronic memory behavior with a high on/off ratio of up to ≈55% and a long retention time over 5000 s response to a light pulse optically triggering MIT. On the other hand, the 2D‐crystalline VO2 film device with a narrow hysteresis width exhibits high performance of photodetection with a responsivity of 316 mA W−1 and response times of ≈1.2 and ≈2 µs at rise and fall, respectively. [ABSTRACT FROM AUTHOR]

Solution‐based methods for fabricating all‐inorganic perovskite film arrays often suffer from limited control over nucleation and crystallization, resulting in poor homogeneity and coverage. To improve film quality, advanced vapor deposition techniques are employed for continuous film. Here, the vapor deposition strategy to the all‐inorganic perovskite films array, enabling area‐selective deposition of perovskite through substrate modulation is expanded. It can yield a high‐quality perovskite film array with different pixel shapes, various perovskite compositions, and a high resolution of 423 dpi. The resulting photodetector arrays exhibit remarkable optoelectronic performance with an on/off ratio of 13 887 and responsivity of 47.5 A W−1. The device also displays long‐term stability in a damp condition for up to 12 h. Moreover, a pulse monitoring sensor based on the perovskite films array demonstrates stable monitoring for pulse signals after being worn for 12 h and with a low illumination of 0.055 mW cm−2, highlighting the potential application in wearable optoelectronic devices. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) materials have attracted extensive attention in the field of photodetection thanks to their unique physical properties. Among them, the PdSe2 nanoflake shows great potential. However, the performance of the PdSe2‐based photodetector with a hetero‐type heterojunction remains poor due to the severe tunneling‐assisted interfacial recombination of photogenerated electron‐hole pairs in the thin bilateral‐depletion heterojunctions. In this work, a novel photodetector with a α‐In2Se3/PdSe2 homo‐type heterojunction for both high‐performance and broadband detection from visible to short‐wave infrared is constructed. The high‐performance of the photoresponsivity of 4.64 × 103 A·W−1, the external quantum efficiency of 1.08 × 106%, and the specific detectivity of 1.55 × 1014 Jones at 532 nm is the result of the homo‐type unilateral‐depletion junction which can promote the effective separation of photogenerated electron‐hole pairs compared to the hetero‐type. Also, adjusting the α‐In2Se3 ferroelectric polarization state further optimizes the unilateral depletion region. In addition, the photodetector can work in a self‐powered mode. This study suggests that the PdSe2‐based homo‐type device has great application potential in the field of 2D optoelectronics. [ABSTRACT FROM AUTHOR]

The results of a study of the optical, electrophotographic and holographic parameters of As-Se condensates from the prehistory of the original bulk materials are presented. It has been established that the electrophotographic parameters of freshly deposited As40Se60 layers change significantly with temperature; the dependences of the maximum charging potential (U0) and the half-decay time of the potential (τ1/2) of electrophotographic As40Se60 layers in the dark on the processing temperature of the melt of the starting material are shown. The dependence of the half-life of the potential in the dark, as well as the properties of bulk samples, has an extremum in the region of Tsub~500°C. The correlation between the dependences of the properties of bulk samples and the electrophotographic parameters of the layers on Tsub indicates that the structural features of the source material in the deposition mode used affect the structure of the films. [ABSTRACT FROM AUTHOR]

In recent years, advances in optoelectronics and electronics have prioritized optimizing semiconductor device performance and reducing power consumption by modeling new semiconductor device geometries. One such innovative structure is the radial p-n junction structure. In this work, we present a concept that submicron three-dimensional simulations were conducted on radial p-n junction structures based on GaAs material to investigate the influence of temperature ranging from 250K to 500K with a step of 50K on the electrophysical distribution, such as space charge, electro-potential, and electric field, in radial p-n junction structures, as well as various forward voltages. In particular, we focus on the shell radius within the structure: 0.5 μm and 1 μm for the shell. The modeling results were compared with the results obtained from solving the theoretical Poisson equation in the cylindrical coordinate system. [ABSTRACT FROM AUTHOR]

Based on the first principles, we have shown that the decisive role in energy transfer from the fluorophore molecule to the carbon substrate (graphene) is played by the Förster-type inductive-resonance energy transfer mechanism. The Förster energy transfer rate can be calculated analytically via Fermi’s golden rule with the momentum-dependent initial final states of the graphene substrates and the HOMO (the highest occupied molecular orbital) and LUMO (the lowest unoccupied molecular orbital) states of the dye molecule. Combining first-principle calculations characterizing the hybrid carbon nanomaterials with tight-binding-based consideration of graphene wave functions allows us to obtain an analytical expression for the Förster energy transfer rate. We constructed graphical dependences of the Förster energy transfer rate at the distance R between substrate (graphene) and dye molecule for several materials. The results obtained can be applied to various hybrids based on carbon nanostructures and in general to the description of energy transfer processes in molecular functionalized nanostructures, once the molecular dipole moment and the substrate - molecule separation are known. [ABSTRACT FROM AUTHOR]

MoS2, a 2D transition metal dichalcogenide, has received significant attention for next‐generation electrical and optical devices due to its excellent optical and electrical properties, including high electron mobility and a direct bandgap. Beyond conventional 2D‐based device architectures, the exploration of 2D and bulk (3D) heterojunctions has revealed unique electronic performance in 2D and structural stability in 3D. III–V semiconductors such as InGaxAs1−x have a direct bandgap with a broad tunability range (i.e., 0.35–1.4 eV), offering an ideal choice for optoelectronic applications. Herein, a type‐II staggered heterojunction between p‐type MoS2 and n‐type In0.53Ga0.47As is demonstrated. The p‐MoS2/n‐In0.53Ga0.47As heterostructure shows the photoresponsivity in the wavelength range from 400 to 1700 nm with typical rectifying diode characteristics. These results highligh the potential of the p‐MoS2/n‐In0.53Ga0.47As heterostructure for high‐performance devices, opening avenues for diverse applications. [ABSTRACT FROM AUTHOR]

This study presents a versatile and efficient method to synthesize large‐size lead sulfide (PbS) quantum dots (QDs) that display emission in the short‐wave infrared (SWIR) region, using accessible and stable diethylammonium diethyldithiocarbamate (C2)2DTCA and octylammonium octyldithiocarbamate (C8DTCA) as sulfur sources. As these sulfur sources enable the formation of well‐dispersed, large‐size PbS QDs in a very convenient way, this method can further be taken up for scale‐up studies. Importantly, this approach allows precise control over QD sizes, thereby enhancing their SWIR optical properties. By adjusting the hot injection temperatures and sulfur source concentrations, different synthesis routes are explored, providing flexibility for the desired QD characteristics. The results presented here offer a promising opportunity to leverage the synthesized PbS QDs in applications such as optoelectronics, sensors, and imaging technology. [ABSTRACT FROM AUTHOR]

The development of CdZnS thin films using the chemical bath deposition process in non-aqueous media is a technological challenge. In this work, 75 millilitres of ethylene glycol and ethanol (1:2 ratios) were used to develop a CdZnS thin film on ITO and FTO glass substrates using cadmium acetate, zinc sulphate, and thiourea. The ideal bath temperature was kept at 130°C and the anneal temperature of the film that had been deposited in the air was maintained at 350°C. The films have been examined using FTIR, WCA, FESEM, and XRD. XRD studies reveal that CdZnS films have a hexagonal crystal structure with a preference for orientation (002) during the deposition and annealing processes and the assessment of the various attributes have been done, such as dislocation density, micro strain, and grain size. FESEM study indicates that as deposited film on ITO glass have smooth surface and grains appear in the form of small needle shape of equal sizes where as FTO substrate reveals the grains of equal size throughout the entire surface in cluster form. It is also confirmed that both the CdZnS films formed on ITO and FTO substrates have hydrophilic quality. The presence of chemical bonds and functional groups was confirmed by FTIR analysis. [ABSTRACT FROM AUTHOR]

We investigate three-dimensional (3D) probe absorption spectrum in a three-level ladder-type quantum dot nanostructure, which is driven by a superposition of three mutually perpendicular standing-wave fields and a traveling- wave field. Due to the position-dependent light-matter interaction, the probe absorption is sensitive to the position in 3D space. It is found that the 3D distribution of the probe absorption spectrum can be easily controlled via adjusting the detuning of the probe field and the intensity of the position-dependent control field. More importantly, the maximal probe absorption can be localized in different positions via tuning the phases of the three standing-wave fields. The scheme may provide some technological applications in solid-state optoelectronics. [ABSTRACT FROM AUTHOR]

Spinel Co3O4 nanoparticles smaller than 10 nm were effectively produced in this study using a Co-precipitation method under optimal conditions. The as-synthesized Co3O4 nanoparticles were found to have great purity and a cubic Co3O4 phase structure with good crystallinity and crystallite size of approximately 9.3 nm, as determined by X-ray diffraction investigation. The Transmission Electron Microscope and Scanning Electron Microscope definitively verified the spherical nanoparticle structure with high density and consistent orientations. The high-resolution-TEM investigation revealed that the produced spinel Co3O4 nanoparticles are single-crystalline and free from observable imperfections. The HR-TEM results indicated that Co3O4 nanoparticles exhibit distinct lattice fringes that correspond to the interplanar spacings identified in the XRD investigation. The energy-dispersive X-ray spectroscopy investigation definitively verified the high purity and stoichiometric production of the nanoparticles. The FT-IR spectra of Co3O4 nanoparticles showed absorption peaks at v1 = 540 cm−1 and v2 = 656 cm−1, confirming the spinel phase structure of the nanoparticles. UV–Vis spectroscopy was utilized to confirm the existence of two distinct band gaps in Co3O4 nanoparticles at energy levels of 3.4 eV and 4.21 eV. Obtaining Co3O4 nanoparticles smaller than 10 nm with specific properties allows for the development of innovative and effective optoelectronic devices with customized features. [ABSTRACT FROM AUTHOR]

This study involves the investigation of the double perovskite A2NbTbO6 (A = Ca, Sr, and Ba) using the PBE-GGA approximation under the quantum-based DFT (density functional theory) within the WIEN2k code. The materials A2NbTbO6 (A = Ca, Sr, and Ba) are cubic crystals with space group Fm3m-225 and non-magnetic behavior. The structural, electrical, optical, and thermoelectric characteristics of the given materials have been investigated. Band gap and density of state calculations are used to explain the electronic properties of the materials under study with the PBE-GGA approximation. The results made it abundantly evident that the materials are pure semiconductors with direct band gaps. Complex dielectric function, refractive index ƞ(ω), extinction coefficient K(ω), optical conductivity σ(ω), absorption coefficient α(ω), reflectivity R(ω), and loss parameter L(ω) are analyzed to explain the optical behavior of the materials. Charge carrier concentration (n), electrical conductivity (σ/t), Seebeck coefficient (S), power factor (PF), thermal conductivity (K/t), specific heat capacity (Cv), and magnetic susceptibility (χ) are investigated to find the material's thermal properties which show the ability of materials in green energy (eco-friendly) production devices and good candidates for optoelectronics especially for solar cell. The BoltzTraP code, which is part of the WIEN2k code, is used to calculate these properties. The cubic compounds Ca2NbTbO6, Sr2NbTbO6, and Ba2NbTbO6 have band gaps of 1.93 eV, 1.89 eV, and 1.87 eV, respectively and are direct band gap materials are confirmed from the band gap structures. By these calculations, all the characteristics are examined to produce new materials for sustainable devices and renewable energy applications like solar cells, and optoelectronics. [ABSTRACT FROM AUTHOR]