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Lead‐based halide perovskites have gained significant prominence in recent years in optoelectronics and photovoltaics, owing to their exceptional optoelectronic properties. Nonetheless, the toxicity of lead (Pb) and the stability concern pose obstacles to their potential for future large‐scale market development. Herein, stable lead‐free Cs3Bi2I9 (CBI) films are presented with smooth and compact morphologies synthesized via chemical vapor deposition (CVD), demonstrating their application as an UV photodetector in a self‐powered way. The self‐powered photodetectors (SPDs) exhibit remarkable characteristics, including a responsivity of 1.57 A W−1 and an impressive specific detectivity of 3.38 × 1013 Jones under the illumination of 365 nm at zero bias. Furthermore, the SPDs exhibit a nominal decline (≈2.2%) in the photocurrent under constant illumination over 500 h, highlighting its impressive long‐term operational stability. Finally, the real‐time UV‐detection capability of the device is demonstrated by measuring the photocurrent under various conditions, including room light and sunlight at different times. These findings offer a new platform for synthesizing stable and high‐quality perovskite films, and SPDs for advancing the development of wearable and portable electronics. [ABSTRACT FROM AUTHOR]

The purpose of our paper is to simulate and optimize the electro-optical characteristics of a reversed Perovskite planar solar cell. Firstly, the synthesis of the CH3NH3PbI3 was exposed. Then, the absorption, reflection and transmission phenomena were studied. The effects of the thicknesses of CH3NH3PbI (d) and HTL (D) layers on the efficiency of the presented have been simulated. Subsequently, the back contact metals effect on Jsc, Voc, FF and was taken into account. For a thickness d=0.6µm, the output parameters reached Voc=1.07V, Jsc=22.75mA/cm2, FF=78% and 1=19.02%. Besides, the efficiency is reduced by the defect density at the CH3NH3PbI3/PEDOT:PSS interface more than that at the PCBM/CH3NH3PbI3 interface and it should be less than 1013 cm-3 to have better solar cell performance. [ABSTRACT FROM AUTHOR]

This study aims to develop of silica (SiO2)/silicon nitride(Si3N4) nanomaterials doped polystyrene(PS) for use in a variety of electronics and optical nanodevices. By casting method, the films of (PS-SiO2-Si3N4) were coursed. The structure characteristics of (PS-SiO2- Si3N4)nanostructures were studied including optical microscopy(OM) and FTIR, and optical characteristics of (PS-SiO2-Si3N4) nanostructures also were studied. The OM confirmed that good distribution of (SiO2/Si3N4)NPs inside the matrix of PS and the FTIR indicates that there is a physical interaction between the polymer (PS) and (SiO2-Si3N4) NPs. The optical characteristics were measured at wavelengths ranging from 260 to 760 nm. The results showed when the ratio reached 6.9 wt% from the SiO2and Si3N4 NPs that the transmission(T) reduced while the absorption(A) increased, this capability qualifies it for use in a variety of optical fields. The energy gap(Eg) of PS when the SiO2 and Si3N4NPs content reached 6.9 wt% decreased, because of this behaviour, (PS-SiO2- Si3N4) nanostructures are regarded as crucial for optical and optoelectronic nanodevices. With increasing concentrations of SiO2 and Si3N4NPs, the optical constants, absorption coefficient, refractive index, extinction coefficient, real and imaginary dielectric constants, and optical conductivity rise. Lastly, the results confirmed the optical properties study that the (PS-SiO2-Si3N4) nanostructures might be used in a variety of nanoelectronics applications. [ABSTRACT FROM AUTHOR]

Efficient characterization of optoelectronic material properties represents a crucial step in the development of next‐generation infrared (IR) materials and devices. For the first time, a sensitive, contact‐free optoelectronic material characterization platform is demonstrated that exploits the unique properties of radio frequency (RF) topological edge states implemented in a topological microstrip waveguide. The topological device is compatible with standard printed circuit board (PCB) processes with no additional materials, stubs, or resonators. The waveguide and topological properties computationally are designed and then experimentally the results are validated with S‐parameter and near‐field measurements. Finally, as a proof of principle, the room temperature spectral response of a micron‐scale thick mid‐wave infrared (MWIR) mercury cadmium telluride (Hg0.70Cd0.30Te) is measured using the topological microstrip and a five‐fold and 20‐fold increase is demonstrated in response when compared to a plain microstrip and trivial bandgap device, respectively. These results open the door to straightforward, low‐cost characterization of optoelectronic films. [ABSTRACT FROM AUTHOR]

Perovskite quantum dot-based light-emitting diodes (QLEDs) have been considered as a promising luminescent technology due to high color purity and wide color gamut. However, the realization of high-performance QLED is still hindered by near-perfect quantum dots (QDs) with efficient and stable exciton recombination behavior. Here, we proposed a ligand compensation (LC) strategy to optimize the QDs by introducing a ligand pair of tri-n-octylphosphine (TOP) and CsBr. The ligand pair could enhance the clarity and colloidal stability of the QD ink, facilitating the fabrication of highly smooth films. On one hand, TOP engages in interactions with Pb and effectively passivates the surface uncoordinated Pb2+. On the other hand, the supplement of CsBr provides a Br-rich environment to reduce Br vacancies (VBr). Through LC, QD films possess a high photoluminescence quantum efficiency of 82% and a shallow hole level, which enables efficient exciton recombination. In addition, the LC makes QD films exhibit stable exciton combination behavior and electrical transport characteristics. Resultantly, the LC-optimized QLEDs show a maximum external quantum efficiency (EQE) of 24.7% and an operational lifetime T50 of 182 h at an initial luminance of 100 cd m−2, which is obviously higher than that of the control device (EQE of 15.8%, T50 of 11 h). The proposed LC strategy for optimizing perovskite QDs presents a novel concept for achieving high-performance QLEDs and holds great potential for widespread application in various optoelectronics. [ABSTRACT FROM AUTHOR]

Using the full potential density functional theory (DFT), structural, electronic and optical properties as well as thermodynamic attributes of GaMF3 (M = Ca and Cd) were studied. In this investigation, electronic and optical characteristics were assessed using the (GGA + U) functional whereas the thermodynamic characteristics of the perovskite were assessed using the Gibbs code. The negative formation energy confirms structural stability. Whereas GaCaF3 shows a direct band gap, while GaCdF3 exhibits indirect energy band gap. Density of states plots indicated the presence of mixed ionic and covalent connections. Optical characteristics are predicted in the energy span of 0–12 eV, including reflectivity, refractive index, absorption coefficients, real and imaginary parts of dielectric functions, and optical conductivity. These materials have a small reflectivity and high absorption in the Ultraviolet region, which makes them good candidates for optoelectronic materials. The negative Gibbs free energy indicate that these materials are stable and can be synthesize at room temperature. This work sheds light on the behavior and composition of perovskites for optoelectronic application. [ABSTRACT FROM AUTHOR]

Herein two stacked nanosheets of lanthanum and silver coated by the thermal evaporation technique under a vacuum pressure of 10–5 mbar are used to form Ag2La compound. Ag2La thin films exhibited crystalline orthorhombic structure with lattice parameters, crystallite sizes and defect densities of a = 6.670 Å, b = 10.386 Å, c = 7.485 Å, 29 nm and 3.99 × 1011 lines/cm2, respectively. The films showed an indirect band gap of 3.25 eV. The band gap contained energy band tails of widths of 0.75 eV. In addition, the dielectric dispersion analyses on the Ag2La film have shown their excellent performance as high k dielectric materials displaying high dielectric constant value of 9.5 at incident light energy of 2.12 eV. On the other hand the optical conductivity and terahertz cutoff frequency spectral analyses have shown that Ag2La films have potentials applications in terahertz technology. The terahertz cutoff frequency varied in the range of 2–9 THz based on the driving light signal energy. As optical resonators they showed high sensitivity to visible and ultraviolet light signals. A respective high drift mobility of ~ 1.5 cm2/Vs and 44 cm2/Vs are estimated for the semitransparent Ag2La terahertz optical filters. The simplicity of producing Ag2La compound, the high dielectric constant values and the semiconducting characteristics of this compound make it attractive for high k-dielectric devices and for terahertz technology applications. [ABSTRACT FROM AUTHOR]

Potassium-based perovskites hold the potential to substantially modify renewable technology by developing eco-friendly devices. A thorough analysis of structural, electronic, optical, transport, and mechanical characteristics of the double perovskites K2AgGaZ6 (Z = Cl, Br) has been executed using the Wein2K code. The stability has been verified by analyzing optimization curves, tolerance factor, and the enthalpy of formation energy. The AIMD simulation further confirms the thermodynamic stability of both compounds. The analysis of electronic band structures indicates that the perovskite K2AgGaCl6 has a bandgap of 1.85 eV, which is reduced to 1.14 eV for K2AgGaBr6. The Kramer-Kronig relation is used to evaluate optical characteristics, which exhibit extensive absorption within the visible spectrum for both materials, enabling their utilization in photovoltaics and optoelectronics. The Boltzmann semi-classical framework is employed to calculate thermoelectric properties. These materials have great potential for renewable energy applications due to their high ZT values, supported by their high Seebeck coefficients and electrical conductivities. The demonstrated mechanical attributes confirm ductility, stiffness, anisotropy, and higher melting temperature. Hence, this study provides theoretical evidence that these perovskite compounds are well-suited for green energy harvesting. [ABSTRACT FROM AUTHOR]

Short foot exercise (SFE) can be combined with dynamic functional tasks such as squats; however, it is unclear whether this combination increases intrinsic foot muscle activity. This study aimed to investigate and compare the abductor hallucis muscle (AbdH) activity during SFE in static and dynamic functional tasks. The AbdH electromyography data of 17 healthy participants with and without SFE were analyzed during static tasks (sitting, double-leg standing, and single-leg standing) and dynamic tasks (double-leg squat, single-leg squat, split squat, and heel-raise). The static tasks were performed with SFE for 5 seconds, and the dynamic tasks were performed while performing SFE. AbdH activity with or without SFE during the task was compared using the Friedman and Wilcoxon signed-rank tests. AbdH activity was significantly greater in conditions with SFE than in those without SFE for all tasks (P < 0.01) except for heel-raise (P = 0.163). AbdH activity during SFE in single-leg standing was significantly higher than that in sitting, double-leg standing, and double-leg squats (P < 0.05). AbdH activity during SFE in the single-leg squat was also significantly greater than that in the sitting position (P = 0.024). No significant differences were found in any other between-task comparisons of AbdH activity during SFE. AbdH activity during tasks without SFE revealed significantly lower levels for sitting and double-leg standing compared to single-leg squat, split squat, and heel-raise (P < 0.001). Additionally, the activity in double-leg squat was significantly lower than in both single-leg squat and heel-raise (P < 0.05). Combining dynamic tasks, except for the heel-raise task, with SFE can increase AbdH activity more than dynamic tasks without SFE. However, clinicians should note that combining dynamic tasks with the SFE may not increase AbdH activity compared to combining static tasks with the SFE. • AbdH EMG was examined during SFE combined with static and dynamic tasks. • Dynamic tasks: double-leg (DL), single-leg (SL), and split squats and heel raise. • Performing SFE during the tasks increased AbdH EMG in all tasks except heel raise. • AbdH EMG during SFE was higher in SL stance than in sitting, DL stance and squat. • SFE during dynamic tasks did not show greater EMG than SFE during static tasks. [ABSTRACT FROM AUTHOR]

Changes in spatio-temporal gait parameters and their variability during balance-challenging tasks are markers of motor performance linked to fall risk. Radio frequency (RF) sensors hold great promise towards achieving continuous remote monitoring of these parameters. To establish the concurrent validity of RF-based gait metrics extracted using micro-Doppler (µD) signatures and to determine whether these metrics are sensitive to gait modifications created by multidirectional visual perturbations. Fifteen participants walked overground in a virtual environment (VE) and VE with medio-lateral (ML) and antero-posterior (AP) perturbations. An optoelectronic motion capture system and one RF sensor were used to extract the linear velocity of the trunk and estimate step time (ST), step velocity (SV), step length (SL), and their variability (STV, SVV, and SLV). Intra-class coefficient for consistency (ICC), mean and standard deviation of the differences (MD), 95 % limits of agreement, and Pearson correlation coefficients (r) were used to determine concurrent validity. One-way repeated-measures analysis of variance was used to analyze the main and interaction effects of visual conditions. All outcomes showed good to excellent reliability (r>0.795, ICC>0.886). Average gait parameters showed good to excellent agreement, with values obtained with the RF sensor systematically smaller than the values obtained with the markers (MD of 0.001 s, 0.09 m/s, and 0.06 m). Gait variability parameters showed poor to moderate agreement, with values obtained with the RF sensor systematically larger than those obtained with the markers (MD of 1.9 %-3.9 %). Both measurement systems reported decreased SL and SV during ML perturbations, but the gait variability parameters extracted with the radar were not able to detect the higher STV and SLV during this condition. The radar µD signature is a valid and reliable method for the assessment of average spatio-temporal gait parameters but gait variability measures need to be viewed with caution because of the lower levels of agreement and sensitivity to ML visual perturbations. This work represents an initial investigation for the development of a low-cost system that will facilitate aging-in-place by providing remote monitoring of gait in natural settings. • A Radio Frequency (RF) sensor was used to estimate gait parameters. • A virtual reality headset was used to deliver visual perturbations while walking. • The RF sensor can estimate gait parameters with good to excellent reliability. • The RF sensor can estimate gait parameters with poor to excellent agreement. • The RF gait variability measures need to be viewed with caution. [ABSTRACT FROM AUTHOR]

Cyclotriphosphazene (CP) is a cyclic inorganic compound with the chemical formula N3P3. This unique molecule consists of a six‐membered ring composed of alternating nitrogen and phosphorus atoms, each bonded to two chlorine atoms. CP exhibits remarkable versatility and significance in the realm of materials chemistry due to its easy functionalization via facile nucleophilic substitution reactions in mild conditions as well as intriguing properties of resultant final CP‐based molecules or polymers. CP has been served as an important building block for numerous functional materials. This review provides a general and broad overview of the synthesis of CP‐based small molecules through nucleophilic substitution of hexachlorocyclotriphosphazene (HCCP), and their applications, including flame retardants, liquid crystals (LC), chemosensors, electronics, biomedical materials, and lubricants, have been summarized and discussed. It would be expected that this review would offer a timely summary of various CP‐based materials and hence give an insight into further exploration of CP‐based molecules in the future. [ABSTRACT FROM AUTHOR]

The field of optoelectronics has undergone a remarkable transformation, fueled by the escalating demand for high-performance devices serving a multitude of applications, such as sensing, imaging, communication, and energy harvesting. This review explores the exceptional growth of optoelectronics and the pivotal breakthroughs that have led to a quantum leap in its capabilities. Novel materials, including two-dimensional wonders like graphene and perovskite solar cells, have played a fundamental role in redefining the boundaries of optoelectronics. These materials exhibit extraordinary optical and electrical properties, enabling the development of devices with unprecedented performance levels. Heterostructures, at the crossroads of different materials, have unlocked new opportunities for device design. By combining materials with complementary properties, researchers have engineered structures that manipulate electron and photon flow, resulting in highly efficient and versatile optoelectronic devices. Innovative device architectures have complemented these breakthroughs, pushing the boundaries of speed, efficiency, and functionality in optoelectronics. Applications across industries, from medical imaging to communication networks and renewable energy systems, are benefiting from these advancements. The article concludes by emphasizing the ongoing potential for innovation in the field of optoelectronics, reminding us of the limitless capacity of science and technology to reshape our world and shape the technologies of the future. [ABSTRACT FROM AUTHOR]

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]

2D carbon nanomaterial graphene has been the subject of intense research on optoelectronic properties. Advancements in graphene-based optoelectronic devices can pave the way for highly efficient, flexible, transparent, compact, spectrally tunable light sources for future commercial applications. In recent years, the field of nanophotonics has progressively developed. Light emissions from graphene-based active materials can provide a leading platform for the development of two-dimensional (2D), flexible, thin, and robust optoelectronics. The exceptional structure of Dirac's electrons in graphene, massless fermions, and the linear dispersion relationship with ultra-wideband plasmon and tunable surface polarities allows numerous applications in optoelectronics and plasmonics. The different dimensions of graphene such as graphene quantum dot and GNR can be reviewed in terms of their recent potential for significant optoelectronic applications. [ABSTRACT FROM AUTHOR]

In this study, the composite P(4ClAni)/CuO, which consists of Poly(4-Chloroaniline) P(4ClAni) and copper oxide (CuO) nanoparticles, was successfully synthesized utilizing a chemically oxidative polymerization approach to be applied in optoelectronics. Both FTIR and EDX analyses showed that CuO has been successfully integrated into the P(4ClAni) matrix. The SEM micrographs reveal uniform loading and distribution of CuO throughout the P(4ClAni) polymeric chains. The UV–Vis absorbance, the Urbach energy, the band edge and a number of carbon clusters were determined. The Tauc relationship was used to determine the band gaps, which revealed a decrease as the CuO concentration increased. The band gap drops from 3.84eV for P(4ClAni) to 3.09, 2.85, and 2.64eV, correspondingly for P(4ClAni)/CuO-1, P(4ClAni)/CuO-2, and P(4ClAni)/CuO-3. While, the Urbach tail is increased from 1.66eV for P(4ClAni) correspondingly to 1.81, 1.85, and 1.93eV. The results show composites made of P(4ClAni)/CuO have better optical characteristics than pure polymer P(4ClAni), suggesting that they can use these composites in optoelectronics devices. [ABSTRACT FROM AUTHOR]

By modulating subwavelength structures and integrating functional materials, 2D artificial microstructures (2D AMs), including heterostructures, superlattices, metasurfaces and microcavities, offer a powerful platform for significant manipulation of light fields and functions. These structures hold great promise in high‐performance and highly integrated optoelectronic devices. However, a comprehensive summary of 2D AMs remains elusive for photonics and optoelectronics. This review focuses on the latest breakthroughs in 2D AM devices, categorized into electronic devices, photonic devices, and optoelectronic devices. The control of electronic and optical properties through tuning twisted angles is discussed. Some typical strategies that enhance light‐matter interactions are introduced, covering the integration of 2D materials with external photonic structures and intrinsic polaritonic resonances. Additionally, the influences of external stimuli, such as vertical electric fields, enhanced optical fields and plasmonic confinements, on optoelectronic properties is analysed. The integrations of these devices are also thoroughly addressed. Challenges and future perspectives are summarized to stimulate research and development of 2D AMs for future photonics and optoelectronics. [ABSTRACT FROM AUTHOR]

Bi4Br4 is a material rich in intriguing topological properties. Monolayer Bi4Br4 film exhibits helical edge states characteristic of a quantum spin Hall insulator, while bulk Bi4Br4 represents a higher-order topological insulator with hinge states. However, direct exfoliation from single crystal can only obtain thin nanowires due to the weak van der Waals forces between Bi4Br4 chains, which limits its optical analysis and application, while the growth of Bi4Br4 thin films is also full of challenges due to the extremely narrow growth temperature range and the accurate control of the BiBr3 flux. Here, we reported the controlled growth of α-Bi4Br4 thin films on intrinsic silicon substrates using molecular beam epitaxy. The growth temperature, BiBr3 flux, and the flux ratio of Bi and BiBr3 were accurately controlled. Then, the morphology, composition, and bonding of the prepared films were investigated using atomic force microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. The growth of large, uniform thin films provides an ideal material platform for studying the physical properties of Bi4Br4. Additionally, we utilized Fourier-transform infrared spectroscopy to explore the film's infrared characteristics, revealing strong absorption in the low frequency range due to the high proportion of one-dimensional topological edge states and laying the groundwork for further exploration of its potential applications in the optoelectronic field. [ABSTRACT FROM AUTHOR]

Chiral hybrid perovskites show promise for advanced spin-resolved optoelectronics due to their excellent polarization-sensitive properties. However, chiral perovskites developed to date rely solely on the interaction between chiral organic ligand cations exhibiting point chirality and an inorganic framework, leading to a poorly ordered short-range chiral system. Here, we report a powerful method to overcome this limitation using dynamic long-range organization of chiral perovskites guided by the incorporation of chiral dopants, which induces strong interactions between chiral dopants and chiral cations. The additional interplay of chiral cations with chiral dopants reorganizes the morphological and crystallographic properties of chiral perovskites, notably enhancing the asymmetric behavior of chiral 2D perovskites by more than 10-fold, along with the highest dissymmetry factor of photocurrent (gPh) of ~1.16 reported to date. Our findings present a pioneering approach to efficiently amplify the chiroptical response in chiral perovskites, opening avenues for exploring their potential in cutting-edge optoelectronic applications. [ABSTRACT FROM AUTHOR]

Motivated by recent experimental and theoretical research on the ability to store and release hydrogen from a hydride perovskite with a large ionic character called RbMgH 3 , we conducted a study using density functional theory (DFT) to investigate the optoelectronic behavior of RbMgH 3 in both Cubic and Hexagonal structures, as well as its phase transition. Our findings reveal that RbMgH 3 exhibits an indirect band gap of 2.41 eV in the Hexagonal phase and a direct band gap of 2.15 eV in the Cubic phase. Additionally, we calculated the Gibbs energy to predict the occurrence of the phase transition. It was determined that RbMgH 3 undergoes a structural transformation from Cubic to Hexagonal at a pressure of 1.78 GPa. This transition has the potential to enhance the storage kinetics of hydrogen, making RbMgH 3 suitable for various applications. • First-principles study of structural phase transition in RbMgH3 perovskite between cubic and hexagonal phases. • Comprehensive investigation of electronic band structures and densities of states for both phases. • Calculation of exciton binding energies and their influence on optical absorption spectra. • Prediction of optical properties: absorption coefficients and dielectric functions. • Insights into potential applications in optoelectronics, photovoltaics and energy storage. [ABSTRACT FROM AUTHOR]

This work focuses on the electronic, optoelectronic, and nonlinear optical properties of the cyclo[2N]carbon series (C10, C12, C14, C16, C18, C20, C22, and C24), and their derivative systems (C8BN, C10BN, C12BN, C14BN, C16BN, C18BN, C20BN, and C22BN) obtained by functionalizing each molecule of the series with the boron–nitrogen (B–N) binomial. The results were obtained from density functional theory and time-dependent density functional theory at the B3LYP-D3, CAM-B3LYP-D3, and ωB97XD/6–31 + G(d) levels of theory. The study found that the cumulative B–N effects on the molecules studied break the centrosymmetry of these molecules while, lowering the energy gap (from 3.11 eV for C18 to 2.80 eV for its derivative C16BN) making these molecules good materials for electronics. The C2N molecules (2N = 4n), namely C12, C16, C20, and C24, and their derivatives C10BN, C14BN, C18BN, and C22BN, are found to have high chemical softness (s), electronegativity (η), and electrophilic index (ω), making them useful materials in optoelectronics. An impressive impact of the B–N cumulative effect on the cyclo[2N]carbon's series is that it significantly generates the first-order hyperpolarizability values. Like C24 of which β = 0.00 a.u. and its derivative C22BN of which β = 8812.77 a.u., value 8 times higher than that of paranitroaniline (β = 1072.44 a.u.), which is the reference compound in nonlinear optics, rendering these molecules interesting for linear and non-linear optical applications. [ABSTRACT FROM AUTHOR]

Variable‐angle spectroscopic ellipsometry is used to determine the room temperature complex refractive index (n˜=n+ik)$\left(\right. \overset{&amp;amp;amp;amp;amp;amp;amp;tilde;}{n} &amp;amp;amp;amp;amp;amp;amp;equals; n &amp;amp;amp;amp;amp;amp;amp;plus; i k \left.\right)$ of molecular beam epitaxy grown GaSb1−xBix films with x ≤ 4.25% over a spectral range of 0.47–6.2 eV. By correlating to critical points in the extinction coefficient k, the energies of several interband transitions are extracted as functions of Bi content. The observed change in the fundamental bandgap energy (E0, −36.5 meV per %Bi) agrees well with previously published values; however, the samples examined here show a much more rapid increase in the spin‐orbit splitting energy (Δ0, +30.1 meV per Bi) than previous calculations have predicted. As in the related GaAsBi, the energy of transitions involving the top of the valence band are observed to have a much stronger dependence on Bi content than those that do not, suggesting the valence band maximum is most sensitive to Bi alloying. Finally, the effects of surface droplets on both the complex refractive index and the critical point energies are examined. [ABSTRACT FROM AUTHOR]

In the current study, the electronic, optical, thermoelectric, and Structural properties of Mg 1−x Zn x O composition have been investigated. The density of states of MgO showed the predominant contribution of Mg- s and O- p orbitals, while for Zn-doped MgO, density of states spectra exhibited strong hybridization among O- p , Mg- s , and Zn- d orbitals. The reduction in band gap with the increase of Zn doping in the MgO host matrix was observed. The thermoelectric properties of pure and Zn-doped MgO samples were measured by utilizing the Boltztrap package. Structural studies showed that the thin films possess the single phase crystalline cubic structure, which retained its stability after Zn incorporation. The results demonstrated that Zn doping into MgO reduced the optical band gap and enhanced the optical properties. The current research focus indicates that Zn-doped MgO thin films with enhanced optical and thermoelectric properties could be potential choices for optoelectronic and thermoelectric applications. [ABSTRACT FROM AUTHOR]

In the current study, films of promising nanocomposites were fabricated from poly-methyl methacrylate(PMMA) filled with chromium oxide (Cr2O3) and silicon carbide(SiC) nanostrucures to employ in several advanced nanoelectronics and optical fields. The PMMA/Cr2O3/SiC nanocomposites have remarkable characteristics compared with other types of nanocomposites included inexpensive, excellent optical properties, good physical and chemical behaviours. The structural and optical properties of PMMA/Cr2O3/SiC nanocomposites films were tested. Results confirmed that the PMMA absorbance increased of 26.3% and 27.6% at λ = 380 nm (UV/spectra) and λ = 580 nm (VIS/spectra) when the Cr2O3/SiC NPs ratio reached of 5.7 wt.%. The PMMA transmittance decreased of 14.8% and 13.4% at λ = 380 nm and λ = 580 nm, these results make the PMMA/Cr2O3/SiC nanocomposites films are promising nanostructures for nanoelectronics and optics applications. The indirect allowed energy gap reduced from 3.82 eV to 3.47 eV with rising concentration of SiC/Cr2O3 NPs to 5.7 wt.%. The optical factors of PMMA improved with rising SiC/Cr2O3 NPs concentration. Finally, the attained results showed the PMMA/Cr2O3/SiC nanocomposites are promising nanocomposites and major key for potential nanoelectronics and optics applications. [ABSTRACT FROM AUTHOR]

Tellurium (Te) has been rediscovered as an appealing p-type van der Waals semiconductor for constructing various advanced devices. Its unique crystal structure of stacking of one-dimensional molecular chains endows it with many intriguing properties including high hole mobilities at room temperature, thickness-dependent bandgap covering short-wave infrared and mid-wave infrared region, thermoelectric properties, and considerable air stability. These attractive features encourage it to be exploited in designing a wide variety of optoelectronics, especially infrared photodetectors. In this Perspective, we highlight the important recent progress of optoelectronics enabled by Te nanostructures, which constitutes the scope of photoconductive, photovoltaic, photothermoelectric photodetectors, large-scale photodetector array, and optoelectronic memory devices. Prior to that, we give a brief overview of basic optoelectronic-related properties of Te to provide readers with the knowledge foundation and imaginative space for subsequent device design. Finally, we provide our personal insight on the challenges and future directions of this field, with the intention to inspire more revolutionary developments in Te-based 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]

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]

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]

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]

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]