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This study investigates the impact of modulating and shaping a laser beam via a phase-only spatial light modulator (SLM) on the intensity of the laser-induced fluorescence (LIF) signal. Different phase modulations ranging from 0 to $2\pi$ are applied to the SLM window to evaluate the effect of the modulated beam on the emitted LIF signal from extra virgin olive oil EVOO samples. The laser beam is also shaped into circular and square geometries with varying diameters to determine the optimum size for maximizing the LIF signal strength. The results reveal that the highest LIF signal intensity could be obtained after modulating the incident laser beam with phase shifts of 0 and $2\pi$, with an improvement factor of approximately 3 for Avanti olive oil and 1.42 for Al Jouf olive oil. Furthermore, laser beam shaping into a circular aperture with a radius of 2.45 mm or a square aperture with a side length of 2.45 mm yields the highest LIF signal improvement, with enhancement factors of approximately 2.9 for Avanti olive oil and 1.42 for Al Jouf olive oil. This work demonstrates the potential of SLM-based beam shaping techniques to optimize LIF measurements by tailoring the wavefront characteristics of the excitation laser source.

An automated-based intelligence approaches have widely used for quantifying In-Vitro Fertilisation (IVF) blastocyst image features that offer automation in morphology assessment as well as embryo selection to improve embryo implantation. Since the IVF blastocyst co-existed three main features of Zona Pellucida (ZP), Trophectoderm (TE) and Inner Cell Mass (ICM), this has made it crucial to consider the informative regions of all features in image morphology assessment. Although the implementation of Navigator-Teacher-Scrutinizer Network (NTS-net) has been detected most informative regions under the guidance of the Teacher network, there still limitation on calculation of the feature extraction process of different blastocyst features that led to poor classification performance. Therefore, this study proposes a new classification model namely NTS-CAM to improve extracted blastocyst features by assigning weights to channel features in channel attention mechanism (CAM) while extracting informative regions of each blastocyst feature. The benchmarking dataset showed significant performance of classification accuracy for ZP, TE, and ICM features with 80.5 %, 67.4 %, and 76.3 %, and the clinical dataset showed 74.1 %, 71.8 %, and 63.5 %, respectively. In conclusion, the proposed NTS-CAM model to predict grade of IVF blastocyst quality has improved the performance compared to classic NTS model. Furthermore, the improved model can be used for clinical decision making as well as for quality control in IVF procedure.

In this paper, an ultra-low thickness with high sensitivity and perfect absorption based on the excitation of Tamm plasmon polaritons and Fabry-Perot resonance for sensing applications is presented. The sensor comprises a graphene sheet, a spacer layer, an analyte region, and a one-dimensional periodic stack of the dielectric and metal layers. The sensor’s performance is evaluated using the transfer matrix method under different conditions, including the presence of the graphene sheet and metallic layers of the periodic stack, a change in the chemical potential of the graphene sheet, the thickness of the layers, as well as the incident polarization and angle. The simulation results show that the presence of the graphene sheet causes stimulation of Tamm plasmon polaritons, and the presence of metal layers simultaneously increases the absorption and decreases the thickness of the sensor. The sensitivity of the sensor is 0.9667 THz/RIU (equivalent to 305 μm/RIU) with an absorption peak of 99.99 %. The use of silicon as the analyte allows the proposed structure to perform as a temperature sensor in the range of 1 THz, which results in a temperature sensitivity of 0.055 THz/°C (equivalent to 16.45 nm/°C). The proposed sensor has the advantages of extremely thin thickness, perfect absorption, high sensitivity, tunability, and fabrication-friendly structure. The proposed sensor has high potential for use in various sensing applications.

The identification of different rubber materials is crucial to ensuring the quality of rubber products. In order to quickly and effectively identify the types of rubber, reduce the impact of counterfeit rubber on the market. This study proposes a rubber identification method based on terahertz time-domain spectroscopy (THz-TDS), Chemometry, and Improved Honey Badger Algorithm (IHBA). Initially, the absorption spectra of eight types of rubber within the 0.2–1.6 THz range are obtained and calculated using THz-TDS. This is followed by data preprocessing using Savitzky-Golay and Principal component analysis(PCA). The optimization effects of genetic algorithm (GA), grid optimization algorithm (GRID), particle swarm optimization algorithm (PSO) and honey badger algorithm (HBA) on support vector machine (SVM) model parameters were compared respectively. The HBA-SVM model achieves 96.88 % recognition accuracy on the prediction set, which is higher than other models and shows excellent parameter optimization ability.To further improve accuracy, Bernoulli chaotic mapping, cosine density factor, and Cauchy mutation are introduced for improvement. Compared with the original model, the IHBA-SVM model improves the accuracy of rubber recognition from 96.88 % to 98.96 %. Furthermore, compared with other models, the IHBA-SVM model achieved the highest classification accuracy. In summary, this study provides technical support and reference for the rapid identification of rubber, which is of great significance for ensuring the quality of rubber products.

This pioneering simulation study explores the potential of perovskite materials, particularly the non-toxic methyl ammonium tin iodide (MASnI₃), in solar cell technology. The investigation focuses on eco-friendly, solution-processed compounds—specifically, WO₃ and In₂S₃ as Electron Transport Layers (ETL) and MoO₃ and WSe₂ as Hole Transport Layer (HTL)—to develop planar n-i-p MASnI₃ perovskite solar cell (PSC) devices. WO₃ is chosen for its solution processing and high electron mobility, while In₂S₃ offers n-type properties, superior carrier mobility, non-toxicity, and thermal durability. MoO₃ and WSe₂ are selected as HTLs for their efficient charge transport capabilities. Utilizing the solar cell capacitance simulator (SCAPS-1D) software, the study systematically evaluates alternative charge-selective materials, considering various parameters such as thickness (0.1 µm to 1.5 µm for absorber and 0.1 µm to 0.35 µm for CTLs), doping concentration (3.2E10 to 3.2E16 for absorber and E16 to E20 for CTLs), defect density, and energy band offset for MASnI₃ PSCs. Four distinct n-i-p device structures are optimized, yielding impressive PCE improvements ranging from 14.63 % to 25.34 %, a significant 3 % enhancement compared to initial results. Notably, the WO₃/MASnI₃/WSe₂ configuration exhibits limitations in electrical performance, while the other optimized structures demonstrate substantial efficiency gains. Further analysis investigates the impact of reflecting coatings (10 % to 90 %), varying contact work functions (5.2–5.8 eV), and temperature (300–400 K) on photovoltaic parameters. Critical factors including energy band offset, recombination current profile, and built-in potential, are meticulously examined, laying the groundwork for advanced PSC implementation. The study culminates in the In₂S₃/MASnI₃/MoO₃ device configuration, which achieves a peak efficiency of 25.34 %, showcasing superior thermal stability and an enhanced fill factor, thus propelling all-inorganic PSCs towards practical implementation.

The present research analyze the performance parameters of a surface plasmon resonance (SPR) biosensor such as sensitivity, detection accuracy, quality factor, and combined sensitivity factor as a function of graphene chemical potential in a metal/2D material/graphene multilayer system. The attenuated total reflection of SPR was studied as a function of the number of graphene sheets for different 2D materials (ZnO, MoS${}_2$, MoSe${}_2$, WSe${}_2$, WS${}_2$) and calculated using the transfer matrix method. It was found that there is a critical value of the chemical potential for which the performance parameters change their behavior abruptly for all type of 2D materials used in the biosensor configuration; this chemical potential value is called critical chemical potential. Furthermore, the number of graphene sheets have a strong effect on the performance parameters. Finally, an analytical expression for the sensitivity was deduced, which allows to explain their behavior for the different 2D materials used in the SPR biosensor.

In this manuscript, a photonic crystal fiber (PCF) based sensor working on surface plasmon resonance (SPR) concept, which is polished at both the sides and consisting of semi-circular grooves is presented for the detection of a broad range of analytes with refractive index (RI) from 1.17 to 1.40. Also, the analysis is carried out for the diagnosis of different blood compositions such as water, plasma, white blood cells (WBCs), hemoglobin (HB) and red blood cells (RBCs). Plasmonic material gold is coated in the semi-circular grooves, which causes the strong SPR effect due to reduced distance between core and analyte resulting in excellent detection of the analytes. Thus, the optimum wavelength sensitivity and resolution in the case of broad analyte range detection with RI from 1.17 to 1.40 is obtained as 13000 nm/RIU and 7.7×10⁻⁶ RIU respectively. Also, blood composition detection using the proposed sensor results in excellent sensing performance with the maximum wavelength sensitivity for hemoglobin-RBCs as 11,500 nm/RIU with finer resolution of 8.69×10⁻⁶ RIU.

In this paper, we explored the effect of adding a nanomaterial layer above the add layer on performance parameter of the considered plasmonic structures (conventional, four and five layer SPR sensors). These structures are stimulated by the COMSOL Multiphysics. We have considered LiNbO₃ as an add layer over a thin film of gold. Further, Graphene, Black Phosphorene, Mxene, MoS₂ MoSe_2, WS₂ and WSe₂ as nanomaterial are considered over add-layer. First, we optimised the thickness gold and LiNbO₃. After that, we calculated reflectance and magnetic field dependent performance parameters, i.e., shift in resonance angle (∆θ_r), full beam width (FBW), sensitivity (S), detection accuracy (DA), quality factor (Q. F.), figure of merit (FoM), field intensity at different interfaces (metal-sensing medium (M-S), metal-dielectric (M-D), dielectric-sensing medium (D-S), dielectric-nanomaterial (D-N), nanomaterial-sensing medium (N-S), and penetration depth (PD) for the considered plasmonic structures. The minimum ∆θr is obtained for conventional structure i.e. 1.492° and maximum ∆θr is obtained for WS₂ as nanomaterial used in five layer SPR sensor i.e., 2.052°. Moreover, FBW is also maximum for five layer SPR sensor with WS₂ as nanomaterial i.e., 6.8430°. Moreover, PD has maximum value for conventional SPR sensor i.e., 190.894 nm, 175.94 nm for four layer SPR sensor and less than 175.94 nm for five layer SPR sensor. This comparative study will help to choose add-layer with nanomaterial over add layer and metal thin film layer in a SPR sensor for the detection of analyte or molecules present in the sensing medium.

"In this paper, the optical design of a Three Mirror Anastigmat (TMA) Telescope is modified by substitution of a convex freeform secondary and optimization carried out to obtain improved performance. The proposed convex freeform surface is precisely manufactured using the bonnet polishing technique and tested with a sub-aperture stitched algorithm, meeting the specified surface accuracy requirements. Further, to validate the design, the realized secondary freeform optic is tested in conjunction with primary and tertiary optics in the conceived TMA configuration. The telescope system performance is established using a double-pass interferometric test setup. The modified design enhances the telescope system's performance in the extended field of view (FoV) from ±2.5° to ±3.5° across the track and from ±0.4° to ±0.6° along the track. Measured performance results demonstrate an average modulation transfer function (MTF) of 0.56 and an average Strehl ratio of 0.64 at all field points. The effective focal length of the system is computed to be 975 mm. In summary, the proposed freeform surface significantly improves the optical system performance within the available real estate of the envisaged space telescope system."

The current study describes the effect of changing a shell thickness on photothermal response of a hybrid nanostructures, using theoretical investigation based on the Finite Element Method (FEM) of the COMSOL multi-physics program. The hybrid nanostructures are the Core/Shell nanoparticles (C/S NPs) and the Core/Multi-Shell nanoparticles (C/MS NPs), with fixed core diameter (30 nm) and variable shell thickness (10–20 nm) to create a new type of hybrid nanostructures usable in photonic and optoelectronic applications. For these hybrid nanostructures, gold (Au) and silver (Ag) as a partner of titanium dioxide (TiO₂) were used in thermo-plasmonic part. Hybrid multi-shell nanostructures consist of silver-gold and gold-silver sandwich with titanium dioxide shell in between, all of which are dispersed in an aqueous medium (n = 1.33). The optical properties, the local field distribution, and local heating control of plasmonic nanostructures have been studied under the influence of illumination at plasmonic wavelengths (405, and 532 nm). The results revealed to a clear tunable and adjustable optical and thermo-plasmonic properties by controlling the structure of the core/shell NPs. This results can be enhanced by changing the shell thickness, shape, size, and the nanostructure. The temperature elevation of the core/shell NPs was about 1–5 °C under different wavelengths of laser irradiation. Based on those results, there is possibility of using the core/shell nanoparticles as an efficient heat source in many applications, such as in the sterilization and disinfection of medical equipments.