Defects and impurities within semiconductor materials pose significant challenges. This investigation scrutinizes the response of a single dopant donor impurity located in nanostructured semiconductors, specifically quantum wells subjected to both harmonic and inharmonic confinement potentials. The primary focus of this inquiry centers on the analysis of binding energy, electron probability distribution, and diamagnetic susceptibility in connection with both the ground (1s) and excited (2p) electron states. Utilizing advanced computational techniques, specifically the Finite Elements Method (FEM) implemented through Python code, this study unveils a marked alteration in the interaction between electrons and impurities when exposed to external fields. Significantly, the characteristics of the confinement potential exert a substantial influence on the explored physical parameters. This research significantly advances our understanding of the interaction between impurities and intense fields, offering valuable insights into solid-state phenomena within low-dimensional systems. Consequently, it contributes to the design and fabrication of next-generation applications in the field of quantum well systems, encompassing areas such as lighting, detection, information processing, sensing, and energy conversion.

The paper deals with the conception and feasibility of the device structure based on the optimized PIN-(In, Ga)N homojunction solar cells. A new and efficient model combining the most realistic ones considering the impacts of band gap narrowing, collection efficiency, Shockley-Read-Hall recombination, and interface polarization is proposed to examine the solar cells' performance numerically. The functioning processes of n-In_0.42Ga_0.58N/i-(In, Ga)N/p-In_0.42Ga_0.58N solar cells at room temperature were investigated by calculating their characteristics for the AM1.5D, AM1.5G, and AM0 American Society for Testing and Materials experimental data. Our results show that the indium content, thickness, and defect density of the intrinsic layer strongly influence the characteristics of the InGaN solar cells. As the In-mole fraction increases, V_oc, FF and efficiency diminish to reach an independent regime for high In-content. A higher-quality 2μm−In_0.43Ga_0.57N for 10¹⁴cm⁻³ defect concentration can exhibit as high an efficiency as ≅11.3%, dropping to ≅4.12% for 10¹⁶cm⁻³ one.

Photonic crystal (PhC) has been studied for their potential to improve the efficiency of Cu₂ZnSnS₄ solar cells by increasing the generated photocurrent by integrating it as a back reflector with almost zero transmission through the absorption active zone of the solar cell. It was found that the thickness of PhC layers greatly affects the width of the photonic bandgap and that increasing the thickness of VO₂ causes it to shift to a higher wavelength range. The PhC layers were added at the back side of the solar cell in two different configurations: (Monoclinic (M) VO₂/TiO₂) and (Tetragonal (T) VO₂/TiO₂) via SCAPS model. The study found that the (M VO₂/TiO₂) configuration led to an enhancement of the device's efficiency from 11.02 to 12.79%, while the (T VO₂/TiO₂) reaches 16.88%. The study concluded that the PhC layers enhance the light-matter coupling and photonic coupling and improvement in the device's performance.

This computational investigation delves into the electronic and optical attributes of InGaN/GaN nanostructures subjected to both harmonic and anharmonic confinement potentials, coupled with the influence of a nonresonant intense laser field (ILF). The theoretical framework incorporates higher-order anharmonic terms, specifically quartic and sextic terms. The solutions to the Schrödinger equation have been computed employing the finite element method and the effective mass theory. Moreover, linear and third-order nonlinear optical absorption coefficients are derived via a density matrix expansion. Our analysis reveals the feasibility of manipulating electronic and optical properties by adjusting confinement potential parameters, system attributes, and laser field intensity. In addition, the ILF induces remarkable modifications, characterized by reduced resonance peak amplitudes and a blue shift in absorption coefficients. Intriguingly, regardless of potential harmonicity, the impact of incident electromagnetic intensity is notably more pronounced in the absence of the ILF. These findings hold significant promise for advancing theoretical predictions, providing valuable insights into the intricate interplay between confinement potentials, laser fields, and their effects on electronic and optical behaviors within nanostructures.

The BTO, BFTC, and BCTF compounds were synthesized by the sol-gel method. The XRD study revealed the formation of single-phase tetragonal perovskite structures with the space group (P4mm). The crystalline parameters were studied as a function of Fe and Co contents and occupation of Ba and/or Ti sites by Fe and Co in the BTO lattice. It was found that the obtained strain increases when Ba²⁺ is substituted by Co²⁺ and Ti⁴⁺ by Fe³⁺. The Raman investigation confirmed the existence of three active modes (B1/E (TO1LO), (E (TO)/A1(TO3), and (A 1(LO)/E (TO), all of which are related to the existence of the tetragonal phase and strongly support the XRD results. The microstructural study showed a clear correlation between the presence of Fe and Co and the grain size distribution. Optical studies revealed the improvement in band gap energy with transition-metal (Fe and Co) co-doped BTO ceramics. The decrease in the band gap is explained by the competing effects of Columbian interactions, microdeformation, and oxygen defects. The results indicate that the presence of Fe and Co dopants enhances the absorption in the BTO ceramic. The dopants demonstrated an effect on thermal conductivity: they decreased the thermal conductivity of BTO, which is in the range of 0.76-2.23 W m^-1 K^-1 at room temperature and 2.02-0.27 W m^-1 K^-1 at elevated temperatures. The microstructure of the manufactured materials and the grain size distribution affect the compressive strength.

The phenomenon of hot carriers, which are generated through the nonradiative decay of surface plasmons in ultrathin metallic films, offers an intriguing opportunity for subbandgap photodetection even at room temperature. These hot carriers possess sufficient energy to inject into the conduction band of a semiconductor material. The groundbreaking use of iridium (Ir) ultrathin film as an ultraviolet (UV) plasmonic material on silicon (Si) for high-performance photodetectors (PHDs) has been successfully demonstrated. Elevating the thickness of the sputtered Ir film to 4 nm yields a notable surge in photocurrent, registering an impressive 600 μA under 365 nm UV illumination with electron mobility of 1.37E3 cm² V⁻¹ s. This PHD exhibits excellent OFF-ON photoresponses at various applied voltages ranging from 0 to 5 V, maintaining a stable photocurrent. Under UV illumination, it displays exceptional performance, achieving a high detectivity of 1.25E14 Jones and a responsivity of 1.28 A W⁻¹. These outstanding results underscore the significant advantages of increasing the thickness of the Ir film in PHDs, leading to improvements in conductivity, detectivity, external quantum efficiency, responsivity, as well as superior sensitivity for light detection.

This study focused on investigating the optoelectronic properties of molybdenum trioxide (α-MoO₃) thin films using the atomic layer deposition (ALD) technique through different cycle numbers and theoretical investigation. Initial band gap calculations using standard DFT with GGA-PBE resulted in a value of 1.19 eV, which deviated significantly from experimental measurements. The GGA + U method with Hubbard U corrections was applied for the first time to improve the accuracy. This refinement led to a more precise band gap value of 3.09 eV, closely matching previously reported experimental data. The electronic parameters of the α-MoO₃ photodetector, such as ideality factor (n), barrier height (Φ₀), and series resistance (R_s), were analyzed using the thermionic emission theory and confirmed by Cheung and Nord's methods. The results demonstrated that the sample deposited with 100 pulses exhibited higher photodetector performance under UV illumination, despite having a lower R_s.

Self-powered UV sensing has enormous potential in military and civilian applications. However, achieving high responsivity and fast response/recovery time presents significant challenges. Self-powered photodetectors (PDs) have several advantages over traditional PDs, including higher sensitivity, lower power consumption, and simpler design. This study introduces a breakthrough self-powered PD that uses a Schottky junction of 2D α-MoO₃/iridium (Ir)/Si ultrathin film to detect 365 nm light at 0 V bias through using atomic layer deposition (ALD) and sputtering systems. The PD response is enhanced by plasmonic Ir-induced hot carriers, enabling detection in a mere 0.1 ms. Incorporating a 4 nm Ir layer boosts the responsivity from 0 to 34 A W⁻¹, and the external quantum efficiency is elevated from 0 to 7E11 under 365 nm light illumination. It also has a high I_ON/I_OFF ratio of 11.22E4 at 0 V. These results make the MoO₃/4 nm Ir/Si structure an interesting option for self-powered PDs with high efficiency, and the use of a simple ALD system for large-scale fabrication of 2D α-MoO₃ on hot carrier Ir plasmonic layer. The findings of this research hold tremendous promise in the field of UV sensing and can lead to exciting developments in military and civilian technology.

The use of electronic devices that incorporate multilayer ceramic capacitors (MLCCs) is on the rise, requiring materials with good electrical properties and a narrow band gap. This study synthesized yttrium-substituted barium titanate (Ba_1-xY_xTiO₃, BYT) using a sol-gel process at 950 °C with varying concentrations of yttrium (0 ≤ x ≤ 0.3). X-ray diffraction analysis showed that the tetragonal phase became less pronounced as the yttrium content increased. The samples had varying grain sizes and porosity, with the BY30%T sample having the narrowest band gap at 2.21 eV. The BYT ceramic with 30% yttrium had a thermal conductivity of up to 7 W/m K and an electrical conductivity down to 0.002 (Ω cm)⁻¹ at 180 °C. The current-voltage characteristics of the BYT MLCC were also studied, showing potential use in next-generation high-capacity MLCCs. This work presents BYT as a promising material for these types of capacitors.