Journal of Computational Electronics最新文献

In this paper, a novel multi-inner analyte channel photonic crystal fiber (PCF) based surface plasmon resonance (SPR) sensor is proposed to analyse plasmodium falciparum parasitized human Red Blood Cells (RBCs) that leads to ague. The full vectorial finite element method (FV-FEM) is employed to investigate the key propagation characteristics of the proposed sensor, such as confinement losses, resonance conditions, sensitivities, resolutions, and their linearities. Metallic plasmonic layers of gold (Au) and silver (Ag) are utilised, with two distinct channel shapes being used (circular and square). There are two alternative scenarios reported to identify the phases of the plasmodium falciparum cycle (Ring, Trophozite, and Schizont) in RBCs. The maximum spectrum sensitivities for circular type analyte channels have been found to be 4500 nm/RIU and 4750 nm/RIU, with resolutions of (2.2 times 10^{-5}) RIU and (2.1 times 10^{-5}) RIU for y-polarized and x-polarized modes, respectively. The spectral sensitivities of the square-shaped analyte channel, on the other hand, are 5300 nm/RIU and 6250 nm/RIU, with resolutions of (2 times 10^{-5}) RIU and (1.6 times 10^{-5}) RIU for y-polarized and x-polarized modes, respectively.

Gallium oxide (Ga₂O₃) is an emerging and promising candidate for high-power and radiation-rich environments, such as space, thanks to its ultra-wide bandgap (~ 4.9 eV) and high critical electrical field (~ 8 MV/cm). Radiation in space, such as protons, alpha particles and heavy ions, can cause serious damage to electronic devices and even lead to permanent damage. However, assessing these devices' reliability and radiation hardness in space-like environments is often expensive and complex. In the present work, we utilize a technology computer-aided design (TCAD) simulation-based framework that uses the concept of non-ionizing energy loss (NIEL) to evaluate the displacement damage in electronic devices under particle irradiation. To assess the radiation tolerance of Ga₂O₃ diodes, first, a TCAD model for Ga₂O₃ Schottky barrier diodes (SBD) is developed and calibrated/benchmarked to an experimental device, followed by irradiation simulations. The results show that Ga₂O₃ SBD can withstand a 5 MeV proton fluence of ~ 10¹⁵ cm⁻² with no change in the forward current voltage (IV) characteristics. This value is significantly higher than that of 4H-SiC (~5 × 10¹³ cm⁻²) and Si (~1 × 10¹²) SBDs with the same ideal breakdown voltage - V_BR (1600 V), demonstrating the potential of Ga₂O₃ as a radiation-hard technology.

Solar cells can be represented by different n-diode models. The most commonly used models are single-diode (SDM), double-diode (DDM), and triple-diode (TDM). The SDM is the simplest and most widely used model with reversible current (I)-voltage (V) expressions. The DDM and TDM are more precise models, but only a few approximate analytical Lambert W approaches are available for current‒voltage (I–V) expressions in the literature. This paper presents approximate analytical invertible voltage‒current expressions (V–I) for DDM and TDM via a g-function. Moreover, this paper presents a new formula for calculating the root mean square error (RMSE) in voltage estimation based on the derived expressions. It also demonstrates the limitations of the Lambert W function and the numerical unsolvability of its solution through examples for these purposes. In addition, the paper discusses and tests analytical and iterative solutions for solving the g-function and provides the MATHEMATICA code for DDM and TDM V–I expressions via the g-function. Therefore, this paper confirms the effectiveness and accuracy of using the g-function in solar cell modeling.

Metasurfaces have garnered significant attention in recent years for their ability to manipulate electromagnetic (EM) wave propagation, owing to their high design flexibility, low profiles, and ease of fabrication. This study proposes the use of polarization-dependent anisotropic metasurfaces to manipulate the phase of orthogonal linearly polarized EM waves, enabling polarization multiplexing with distinct functionalities based on incident polarizations. Additionally, the proposed metasurfaces enable the generation of single pencil beams, multiple pencil beams, circularly and elliptically shaped radiation beams, offering versatile polarization manipulation capabilities. The radiation theory of planar array antennas was employed to predict the far-field patterns of the metasurfaces, demonstrating satisfactory agreement with simulated results and affirming the feasibility of the proposed method. The ability of focusing the incoming EM wave into a focal point or multi focal points and generating vortex beam carrying orbital angular momentum (OAM) under the incidence of orthogonal linearly polarized waves are also demonstrated by the proposed anisotropic metasurfaces. This proposed metasurfaces pave the way for the development of multifunctional metadevices capable of advanced EM regulation through polarization and phase modulations in free space, with potential applications in wireless communication, imaging, and radar systems.

In this paper, the characteristics of the fundamental mode of surface plasmons in a circular cylindrical three-layer graphene waveguide structure are investigated. By using Maxwell equations in the cylindrical coordinate system and applying the boundary conditions, the dispersion relation has been derived for the fundamental mode. In the proposed model, along with the electric field distribution in the waveguide, the effect of different model parameters on the dispersion curve has also been investigated. For instance, the effect of chemical potential, temperature and the separation between the first-second and second-third layers of the graphene has been shown and discussed in detail. Furthermore, the effect of chemical potential, temperature and separation between the first-second and second-third layers of the graphene on the propagation length and phase speed is also discussed.

The pursuit of increasingly efficient and cost-effective solar energy solutions has driven significant advancements in photovoltaic (PV) technologies over the past decade. Among these innovations, bifacial solar cells, which capture sunlight from both the front and back surfaces, with front surface texturing and rear-side optimization playing crucial roles, present a promising avenue for enhancing efficiency compared to conventional designs. The effectiveness of these cells, however, is largely dependent on the optimization of rear surface properties and the material characteristics employed. This study investigates into the pivotal role of surface texture, particularly on silicon wafers, in shaping key performance metrics such as open-circuit voltage, short-circuit current, fill factor, and overall efficiency. Given the complex interdependencies among these parameters, machine learning (ML) tools, specifically random forest regression models, have been utilized to decode these intricate relationships. The findings underscore the significance of surface texture in modulating reflectance from both the rear and front surfaces, which in turn influences the overall performance of the solar cells. By applying ML models, this research provides an improved understanding of the impact of surface characteristics, thereby offering valuable insights into the optimization of design and material selection for next-generation high-performance solar cells. This ML optimization study indicates that the pyramid structures with a height of 3 μm and a base angle of 62° can significantly reduce reflectance to 9% while maximizing solar cell efficiency to 23.61%, marking a substantial advancement over existing designs. This model achieves 75% accuracy on synthetic test data and 78% on experimental data reinforcing model’s applicability despite typical ML limitations in PV systems.

This study introduces a distinctive entwined photonic crystal fiber (PCF) featuring two distinct and independent directed mode sections, collectively supporting a total of 112 orbital angular momentum (OAM) modes, comprising 76 + 36 modes. The confinement loss (CL) ranges approximately between (2.49701times 1{0}^{-11}) and (9.13425times 1{0}^{-9} text{dB}/text{m},) while highest attained OAM purity is (99.31969%) and (98.99258%) at (H{E}_{2, 1}) mode, respectively, for both inner and outer rings. All the modes demonstrate ERIDs exceeding (1{0}^{-4}), and minimum dispersion variation observed is (-856 text{ps}/text{km}-text{nm}). Additionally, we achieved an outstanding isolation performance with the highest attained ISO reaching (294 text{dB}) at ({text{HE}}_{9, 1}) mode and observed a substantial effective mode area of 9.15 μm² and 25.8μm², respectively, for inner and outer rings. This research leverages COMSOL Multiphysics' finite element method (FEM) and perfectly matched layer (PML) capabilities alongside MATLAB processing to calculate all key properties of the proposed fiber. Therefore, the suggested PCF demonstrates promising prospects for extended-range, high-capacity data transmission within optical communications and applications related to OAM sensing.

This study investigates the influence of external hydrostatic pressure on the mechanical, electronic, and magnetic properties of cubic GdAlO₃ using density functional theory (DFT) and Monte Carlo (MC) simulations. Mechanically, upon pressure increase, a sizable increase in the elastic constants C₁₂, C₁₁, and C₄₄, as well as in bulk, Young's, and shear moduli of GdAlO_3, is observed. This indicates an enhanced stiffness and resistance to deformation upon pressure increase. The band gap shows a notable increase in pressure, which is useful in tuning the electronic properties of specific electronic devices for potential applications. In addition, a stable overall magnetic moment is observed under pressure variation, with increased exchange interaction parameters for Gd-Gd pairs, indicating more robust ferromagnetic ordering. Furthermore, the Monte Carlo simulation revealed increased Curie temperature (T_C) from 67K at 0 GPa to 142K at 90 GPa, underscoring strengthened magnetic interactions and thermal resilience under compression.

Metal chalcogenide perovskites have a number of benefits over lead-halide perovskites, including superior moisture resistance, light-induced degradation together with nontoxic elemental composition, higher absorption, and exceptional carrier transport properties. These materials have orthorhombic phase Pnma and are potential candidate materials to be used as absorber materials in solar cells. In this study, we propose metal chalcogenide perovskites CaZrX₃ (X = S, Se) as a candidate absorber material. Therefore, the investigation of the structural, electrical, optical, thermal, and thermoelectric properties of CaZrX₃, where X = S, Se, is being carried out using first principles methods. These proposed semiconducting compounds will meet the requirement for stability against volume change. These materials show a direct band gap of 1.812 eV and 1.117 eV at the Γ point. To better understand the optical transitions in the material, the real and imaginary parts of the dielectric function have been calculated. The remarkable absorption coefficient ((alpha )) exceeding 10⁵ cm⁻¹ above photon energy exceeding bandgap indicates that the materials are suitable for the visible light absorption. For the estimation of photovoltaic performance of CaZrX₃ (X = S, Se) and to demonstrate the high photo-absorptivity, the spectroscopic-limited maximum efficiency has been calculated. The results show a maximum photovoltaic efficiency of 26.4% and 32.4% for CaZrS₃ and CaZrSe₃ respectively at the thickness L = 100 nm. We have also calculated the thermoelectric coefficients. These perovskites are gaining more attention as a thermoelectric material because of their higher Seebeck coefficient, and ultra-low thermal conductivity.

Recent advances in VLSI technology have led to the introduction of Quantum dot Cellular Automata (QCA) technology as a possible alternative to CMOS technology. This is owing mostly to its tiny feature size, high operating frequency, and low power consumption. During the preliminary research stage, QCA has been used to execute diverse models of combinatorial and sequential circuits, which serve as the fundamental functional components in a wide range of applications. Currently, research is focusing on the implementation of application-oriented architectures using QCA. The motivation behind this research work is to incorporate Galois Field (GF) functions into the AES Mix- Columns operation. We have proposed an Xtime multiplier implemented using QCA technology and analyzed the multiplier using various XOR models of QCA.