Optical and Quantum Electronics最新文献

This paper introduces an innovative approach for addressing the Poisson equation in simply and doubly connected 3D domains with irregular surfaces, which has significant implications in various scientific and engineering fields, such as irregular cross-section optical waveguides and electromagnetic wave propagation. The Poisson equation is extensively utilized across disciplines like physics, engineering, and mathematics, and its solution offers insight into diverse physical phenomena. The solution to the Poisson equation is helpful in constructing potentials crucial for the comprehension and design of optical and electromagnetic systems. The application of Radial Basis Functions (RBFs) collocation method with changeable form parameters presents novel opportunities for precise and efficient resolutions of this significant equation. Our methodology is relevant to both simply and doubly connected three-dimensional domains with irregular surfaces, frequently seen in various practical applications, such as complex waveguide geometries. Seven instances are presented for various complex simply and doubly connected 3D domains, illustrating the efficacy of the suggested Poisson solver in generating potentials to improve the precision and efficiency of the method. The proposed method can be considered as a benchmark solver for such type of problems appearing in optics and electromagnetic wave engineering. keyword: Radial Basis Functions, Simply Connected Domains, Double Connected Domains, Variable shape parameter, Three dimensional Laplace equation, Three dimensional Poisson Equation.

Silver nanoparticles (Ag NPs) were deposited onto a 2 at.% Tungsten (W)-doped ZnO (WZO)/p-Silicon (p-Si) UV photodetector using a cost-effective sol–gel method. Top-view scanning electron microscopy (SEM) images confirmed the uniform coating of Ag NPs. Cross-sectional SEM analysis revealed a WZO film thickness of 167 nm, including the Ag NP layer. UV–Vis spectroscopy demonstrated high transparency with an average value of 79.5% for the Ag NPs-coated WZO film. The bandgap energy of this film was calculated to be 3.17 eV. The fabricated photodetector, comprising the Ag NP-modified WZO film and p-Si substrate, exhibited superior performance due to enhanced optical and electrical properties. Notably, the device achieved a responsivity (R*) of 4.83 A/W, a sensitivity (S*) of 60.82, and a detectivity (D*) of 5.06 × 10¹² Jones. Compared to the unmodified WZO/p-Si device, the Ag NP-coated photodetector displayed significant improvements: a 26% increase in R*, a 79% increase in S*, and a 53% increase in D*. These findings highlight the potential of incorporating metal nanoparticles into photosensitive devices to optimize light-matter interactions.

Recently, lead-free double perovskites have gathered significant attention in the research community for their unique way of behaving, and multipurpose applications in memory devices, different types of fuel cells, catalyst electrodes, solar cells, spintronics, and optoelectronics devices. This study widely explores the structural, electronic, optical, elastic, mechanical, and thermodynamical properties of lead-free double perovskite compound La₂NiMnO₆ (LNMO) using density functional theory (DFT) computations along with a precise way of handling electron interactions known as the generalized gradient approximation (GGA), specifically utilizing the Perdew–Burke–Ernzerhof (PBE) method under differed pressure conditions. It goals to boost the characteristics of LNMO by applying pressure and offers valuable supervision for future researches. LNMO displays varied optical and electronic individualities, including Drude-like metallic behavior, variation of refractive index with pressure, higher reflectivity in UV region, pressure-dependent enhanced conductivity and amended applications in optoelectronics. We explore how La₂NiMnO₆ reacts to stress, distortion, and shear forces, revealing its strength and stability. The analysis of its mechanical appearances uncovers La₂NiMnO₆'s pliability and the modification to ductility from brittleness as pressure rises, leading to improved stiffness and flexibility. Additional investigation on the direction-dependent mechanical property discloses the transition from anisotropic to isotropic under increasing pressure. These findings not only expand our fundamental comprehension of La₂NiMnO₆ but also carry noteworthy practical inferences for its application across various technological applications.

This paper presents a revolutionary breakthrough in wearable antenna technology through an ingeniously engineered arrowhead-shaped textile butterfly design, fabricated on an eco-friendly jean’s substrate marking a paradigm shift in flexible electronics and communication networks. This textile antenna's distinctive morphology transcends conventional designs by seamlessly fusing biomimetic principles with cutting-edge electromagnetic architecture for wearable antenna applications, delivering unprecedented flexibility and conformability while maintaining superior performance metrics. Rigorous electromagnetic simulations and prototype validation demonstrate exceptional results: an ultra-wideband frequency response spanning 2.359–16.76 GHz, coupled with a remarkable peak gain of 6.9 dB and a ground-breaking bandwidth enhancement of 150.64%. The antenna's biomimetic butterfly topology revolutionizes omnidirectional connectivity while achieving unprecedented miniaturization, making it ideal for vital sign monitoring systems. Most significantly, the design incorporates an innovative electromagnetic field distribution technique that yields exceptionally low Specific Absorption Rate values, surpassing FCC safety standards. This breakthrough enables transformative applications in clairvoyant medical monitoring, facilitating next-generation vital sign monitoring with zero-latency data transmission and minimal electromagnetic interference, thereby pioneering new frontiers in personalized healthcare diagnostics and real-time patient monitoring systems. The integration of flexible electronics with this innovative textile antenna design represents a significant advancement in wearable technology, offering robust solutions for future healthcare applications.

In this study, we adopted a 16-atom simple cubic supercell based on the special quasi random structure approach of Zunger et al. to investigate the structural, electronic and optical properties of InP_xAs_ySb_1-x–y quaternary alloys in zinc blende phase. The calculations were performed using the full potential linearized augmented plane wave (FP-LAPW) method within density functional theory (DFT). We employed the local intensity (LDA) and generalized gradient approximation of Wu and Cohen (GGA-WC) to calculate the structural parameters. Both schemes (EV-GGA) and (TB-mBJ) were used to describe the optoelectronic properties. Our calculations show that the lattice constant value of InP_xAs_ySb_1-s-y quaternary alloys decreases almost linearly with increasing P concentration. Electronic results showed that InP_xAs_ySb_1-s-y quaternary alloys exhibit a direct band gap semiconductor for all P concentrations. Furthermore, we observed that the direct band gap of quaternaries increases linearly with P concentrations. The optical properties of InP_xAs_ySb_1-s-y quaternaries, including the dielectric function, optical conductivity, absorption coefficient and the complex refractive index were predicted and discussed in detail. The obtained results make these compounds very promising for optical telecommunications.

A novel framework based on combining the You Only Look Once-CSE (YOLO-CSE) model is implemented in this paper with Communication Visible Light (CVL) and Multiple Access non-orthogonality (MANO-CVL) for Multiple Input and Output (MIMO). The main goal of the proposed model is to decrease the detecting error in the received bits and distinguish between noise signal and correct bits. The YOLO-CSE model uses the Yolov5 model as a backbone. Two sorts of regulation are applied; position modulation (L-PPM) with different L and users, inside a Comparable Gain Combiner (CGC) at the recipient. This framework thinks about (n) and (m) clients in the ideal and non-ideal Cancellation of Successive Interferences (CSI). Because of the YOLO-CSE model, the error execution is additionally considered versus the power portion coefficient (α) for (n) and (m) clients switching keying (OOK) balance Single Input and Output (SISO), ((n times n), and left( {m times n} right)) for CVL based on utilizing the MANO and MIMO frameworks. The proposed model focuses on the significant highlights that have been removed from the dataset by utilizing the Convolutional unit (CBAU). The Fast-Pooling Spatial Pyramid (SPPF +) is likewise applied to the extricated highlights to reuse them. In that unique situation, the exponential block is coordinated to enact the capability for additional exact outcomes. The modified model, YOLO-CSE outperforms the other models in the literature by 18% outperform the other models in the literature.

Thin films of 5,10,15,20-tetraphenyl-21H,23H-porphine vanadium (IV) oxide, VOTPP, were placed on glass with an overall thickness of 495 nm utilizing the thermal deposition process. The films underwent annealing at various temperatures (323, 373, 423, 473, 573 K) for 3 h. The thermal behaviour of VOTPP powder was tested by DTA. The crystalline molecular structure, and surface morphology of as-deposited and annealed films were examined utilizing XRD, SEM, and AFM. The crystallinity of VOTPP film was enhanced and the crystallite size grew by boosting the annealing temperature. The RMS roughness of annealed film at 573 K is 14.87 nm. Optical parameters of as-deposited and annealed VOTPP films were determined by spectrophotometric measurements in the spectrum of (200–2500 nm). The absorbance spectrum of VOTPP films is characterized by the Soret band, which exhibits Davydov splitting into two peaks, B_x and B_y in the annealed films at 473 and 573 K. Additionally, Q and N bands are observed. Annealing reduces both the linear and nonlinear refractive index, as well as the dispersion parameters. Calculations for molar refractivity and absorptivity, nonlinear parameters, and optical conductivity at different annealing temperatures have been done. Additionally, the energy loss functions at different annealing temperatures were obtained. The electronic transition is indirectly allowed. Optical energies such as ({E}_{g}^{onset}), ({E}_{g}^{opt1}), ({E}_{g}^{opt2}), and ({E}_{U}) were observed to reduce as the annealing temperature elevated. All the optical parameters were compared with other porphyrin derivatives. This study demonstrates that thermally annealing is an efficient method in enhancing the optical and synthetic characteristics of VOTPP films, which serve as a viable absorbing layer in renewable energy systems.

The study investigates the solid polymer composite (SPC) made using solution casting with PVA as the host polymer and KI as the dopant. The SPC was exposed to electron beam doses ranging from 0 to 300 kGy to study its microstructural, optical, thermal, electrical, and dielectric properties. XRD, FTIR, and TGA were used to study the structural and thermal properties. Results showed variations in crystalline phase, charge transfer complex formation, and defects due to crosslinking and chain scission processes. The activation energy for thermal decomposition values matches the onset temperature. UV–Vis studies revealed changes in optical properties with radiation dose, attributed to molecular ordering changes, defects formation, and charge transfer complexes. Electric and dielectric properties were studied using impedance spectroscopy. The highest ac conductivity was achieved for 300 kGy-irradiated SPC, attributed to free radical production. The correlated barrier hopping model was found to be the best fit for characterizing the electrical conduction mechanism of the system. Dielectric measurements revealed non-Debye behavior and substantial dielectric dispersion in the frequency range, increasing with irradiation dose. The results suggest the SPC is a potential candidate for solid-state energy storage and conversion applications.

This study delves into the significant role played by Quantum Dot Semiconductor Optical Amplifiers (QD-SOAs) in meeting the ever-growing bandwidth demands. QD-SOAs offer a unique blend of cost-effectiveness, integration capabilities, wide bandwidth, rapid responsiveness, robust power output, stability, and spectral adaptability, driving notable advancements in optical communication systems. In this work, we introduce a novel two-wavelength amplifier structure based on Quantum Dot Semiconductor Optical Amplifiers (QD-SOAs) that utilizes quantum dots of different sizes to achieve efficient amplification at specific mid-infrared wavelengths. This innovative approach, which incorporates quantum dots with varying sizes, enables enhanced performance by optimizing the amplification process for each specific wavelength. Furthermore, this work demonstrates the use of tailored optical pumping mechanisms that enhance the carrier recovery process and reduce carrier relaxation times in the active region. This novel optical pumping technique leads to a significant increase in the efficiency and speed of the amplifier, distinguishing this study from others in the field. Simulation results provide detailed insights into the complex interplay between carrier interactions and gain spectra, offering a comprehensive understanding of QD-SOA operational dynamics. The proposed Quantum Dot Semiconductor Optical Amplifier (QD-SOA) achieves significant advancements in optical communication, offering maximum amplification rates of 26.9 and 19.9 times for QD₁ and QD₂, respectively, and bandwidths of 12 THz and 15 THz. The study highlights the role of quantum dot size, homogeneous and inhomogeneous broadening, and optical pumping in enhancing gain and performance, demonstrating the potential of QD-SOAs for high-gain, wide-bandwidth applications in photonic systems.

Glass containing zinc-lead boroselenate glasses with the formula 10ZnO–20PbO₂-xB₂O₃–(70 − x)SeO₂ (where 10 ≤ x ≤ 60 mol%) were prepared using the conventional melt quenching method. Several physical properties, including density and molar volume, were determined. Glass transition temperature (T_g) was investigated using differential scanning calorimetry (DSC), revealing a decrease in T_g from 347 to 426 °C as the B₂O₃ content increased. Optical absorption studies showed that as the SeO₂ content decreased, the cutoff wavelength increased while the optical band gap energy (({E}_{opt})) and Urbach energy (({Delta E})) decreased. The ({E}_{opt}) values for these glasses ranged from 2.699 to 2.091 eV, while ΔE values fell between 0.232 and 0.351 eV. FTIR measurements revealed that SeO₃ tetragonal and SeO₄ pyramidal units, as well as BO₃ and BO₄ units, were present in the network structure of these glasses. Additionally, Raman spectra identified distinct structural units. The FTIR and Raman spectra did not show any specific SeO₂ absorption bands. However, the presence of SeO₂ in the glass matrix changed how PbO₂, ZnO, and B₂O₃ were absorbed.