Manipulating unintentional doping in graphene layers, which is influenced by environmental factors and supporting substrates, is of significant concern for the performance and advancement of graphene-based devices. In this context, laser-induced tuning of charge carriers in graphene facilitates the exploration of graphene’s properties in relation to its surroundings and enables laser-assisted functionalization. This has the potential to advance optoelectronic devices that utilize graphene on transparent dielectric substrates, such as Al 2 O 3. In this work, laser power (P L) in Raman spectroscopy is used as a convenient contactless tool to manipulate and control unintentional carrier concentration and Fermi level position (E F) in graphene/α-Al 2 O 3 (G/Al 2 O 3) under ambient conditions. Samples are annealed at 400 C for two hours in an (Ar+ H 2) atmosphere to remove any chemical residues. Analysis of the peak …

The rapidly developing field of topological photonics has the potential to revolutionize the design and operation of optical systems. This study presents a novel approach for constructing a resilient sensor based on topological resonance. The coupling of the photonic crystal waveguide (PCW) with the topological corner state (TCS) within the structure forms the proposed sensor. The PCW provides a well-defined propagating mode, while the TCS is a localized mode that is topologically protected against perturbations. The coupling between the two modes contributes growth to a Fano resonance and results in a sharp and narrow spectral feature sensitive to the refractive index variation of the surrounding medium. The proposed sensor possesses a high sensitivity of ∼461.96 nm/RIU with a high Q-factor \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts …

Abstract Herein, the anodization of 2.6 μm Al-0.2 at.% Cu (Al-0.2 Cu) films on TiN/p-type Si substrate were performed using common acidic mediums at different ranges of anodization voltage (V a) to produce porous anodic alumina (PAA) nanostructures with high porosity. The anodization of Al-0.2 Cu in 1 M H 2 SO 4 at V a range of 10–30 V produced a higher oxide thickness, and hence, a higher volume expansion factor, compared to the anodization in 0.75 M H 3 PO 4 at V a range of 100–140 V. The increase in V a, as expected, increases the inter-pore distance, pore size, and porosity of the PAA and improves the anodization rate. The optical sensing performance of the synthesized PAA under different conditions was investigated. The maximum surface wettability was attained for PAA anodized in 1 M H 2 SO 4 at 20 and 30 V. Moreover, the Vickers hardness (HV) of PAA was improved by forming a thin alumina …

Solar light-driven water splitting offers a sustainable pathway for energy conversion. This study presents a straightforward electrodeposition method for decorating ZnO nanosheets with CdS nanonoodles, varying the deposition time. Structural and morphological analysis confirmed the formation of a crystalline, Cd-rich hexagonal CdS phase on the ZnO nanosheets, exhibiting a unique nanonoodles morphology. The thickness of the CdS/ZnO nanonoodles gradually increased to 30 μm with extended deposition times. Notably, the valence band of the hybrid CdS/ZnO nanonoodles exhibit a lower binding energy compared to both CdS nanonoodles and ZnO nanosheets, highlighting interfacial charge transfer and enhanced synergy. The hybrid CdS/ZnO nanonoodle photoanode, fabricated with a 60-min deposition time, exhibits a reduced band gap of 2.8 eV compared to the 3.2 eV band gap of the pristine ZnO nanosheets. This reduction in the band gap indicates enhanced solar light absorption capabilities. The CdS/ZnO nanonoodles demonstrate a gradual improvement in the photoelectrochemical water splitting efficiency with increasing deposition time. The hybrid photoanode achieves a remarkable photocurrent density of 9.49 mA cm⁻² at 1.23 V vs. reversible hydrogen electrode (RHE), representing a 20-fold increase compared to the ZnO nanosheets (0.46 mA cm⁻²) and a 7-fold increase compared to the CdS nanonoodles (1.45 mA cm⁻²). This heterostructured CdS/ZnO nanonoodles hybrid photoanode achieves an impressive conversion efficiency of 9.21 % at 0.4 V vs. RHE.

Ground-penetrating radar (GPR) is a noninvasive near-surface geophysical method. This method
is beneficial for imaging, characterization, and intrasite analysis of buried archaeological remains
within culture sediments at Ginah archaeological site. The investigation of these targets has intrinsic
value and has never been conducted at this site. In this study, GPR can be utilized to conduct a more
focused survey on individual features and understand their structures, dimensions, and depths. The
field survey on the studied area was conducted by SIR 4000 with 200 and 400-MHz antennae using
RADAN 7 software. The processed GPR radargrams, depth slices, and 3D subvolumes are used to
illustrate typical georadar facies associated with the stratigraphy and architectural elements of the
buried archaeological remains. The facies analysis helps to identify the nature of cultural sediment,
constructed materials, and the anticipated archaeological artifacts at various depths. These detected
features are beneficial for presenting a compelling justification of nature, constituents, architectural
patterns, and historical cultures. Also, this information is used to make guesses based on what is
seen in the field and the archaeological history found in the ruins of Ginah, Al-Ghuieta, and Al-Zayyan
fortresses along the Darb El-Arbine route. This information is essential to assume different successive
ancient periods at the examined site, which can help specialists hasten their excavations.