DEPARTMENT OF PHYSICS

Zinc sulphide (ZnS) thin films were successfully deposited on glass substrates using an improved solution growth technique (SGT) at a constant temperature of 50 °C for three hours, with bath molarity varied between 0.03 M and 0.15 M. The optical and solid-state characteristics of the films were systematically investigated to evaluate the influence of precursor concentration on their structural and optoelectronic performance. Spectral analyses revealed that absorbance increased while transmittance generally decreased with rising molarity, indicating enhanced light absorption due to improved film density. The absorption coefficient (α) and refractive index (n) exhibited molarity-dependent variations consistent with changes in surface uniformity and crystallinity. Calculated optical band gaps (Eg) ranged between 3.47 eV and 3.77 eV, signifying direct allowed transitions typical of ZnS semiconductors. Notably, films prepared at 0.12 M displayed optimal optical properties, balancing high transmittance with suitable band gap energy for potential application in solar cells and other optoelectronic devices.
The results confirm that controlled bath concentration in SGT offers a simple and effective route to tailoring ZnS thin films with desirable optical and solid-state characteristics for functional material applications.

This research explores the photon (γ) as the gauge boson responsible for mediating the electromagnetic force, framed within Yang–Mills gauge field theory. The work investigates how U(1) gauge symmetry naturally gives rise to the electromagnetic field and explains the masslessness, spin-1 nature, and non-self-interaction of the photon as direct consequences of unbroken gauge invariance.

Through comparative analysis between Abelian and non-Abelian gauge theories, the study demonstrates that while Yang–Mills fields (SU(2), SU(3)) yield self-interacting gauge bosons, the Abelian U(1) symmetry of electromagnetism produces a linear, non-self-interacting field—the classical Maxwell equations emerging as a special case.

The findings confirm that the photon’s existence and properties are not empirical accidents but logical necessities of gauge principles. Ultimately, this project underscores the profound unity between electromagnetism and the broader framework of modern gauge theory, situating the photon as a fundamental manifestation of symmetry in nature.

Perovskite materials made of lead telluride (PbTe) have gained a lot of attention from researchers because of its potential uses in photovoltaics, optoelectronics, and thermoelectrics. They cannot, however, be fully utilized in device applications due to issues such as structural instability, mechanical constraints, electronic flaws, and suboptimal optical performance. In order to solve these problems, we comprehensively examine the structural, mechanical, electronic, and optical characteristics of PbTe perovskite using first-principles density functional theory (DFT) computations. Through the analysis of elastic constants, and formation energies, our study unveils the basic stability criteria. The mechanical resilience of the material is assessed by evaluating its mechanical properties, such as bulk modulus, shear modulus, and Poisson's ratio. Additionally, the nature of bandgap engineering and defect tolerance can be understood through the use of density of states and electronic band structure simulations. The dielectric function and absorption coefficient are examples of optical response functions that are calculated to maximize light-harvesting efficiency. Our findings point to potential strain engineering and doping techniques to improve PbTe's stability, electrical performance, and optical activity, hence increasing its suitability for use in next-generation energy and optoelectronic applications.

This research focuses on the design and implementation of a wireless resistivity meter using discrete components. The system addresses the limitations of traditional wired resistivity meters by integrating a wireless transmitter and receiver for efficient data acquisition and portability. The transmitter processes sinusoidal and square wave signals from a signal generator and wirelessly transmits the data to the receiver for analysis. The wireless resistivity meter was evaluated through experimental tests to validate its accuracy, reliability, and operational range. Results demonstrate that the system effectively captures and transmits geophysical data with high precision, making it a significant advancement over conventional wired systems. Key features of the system include real-time data storage and export capabilities, compatibility with modern software tools like LabVIEW Signal Express, and robust performance across varying field conditions.

This study has used the recently established combination between EAM and
the TB-SMA scheme to determine the n, p, q parameters values needed for the
calculation of total energy of the three FCC metals which include Ag, Pd and Pt. The EAM and TB-SMA was established to replace the old approach of determining parameters for calculating total energy because of its improved computational efficiency and accurate results. The Microsoft excel programming language has been employed in this study to reproduce results with good accuracy as compared with previous studies using other programming software.

This study examined the use of Electrical Resistivity Tomography (ERT) to investigate the subsurface lithology in Ugbogiobo, Ovia North East Local Government Area of Edo State. The research aimed to determine the variation in subsurface materials and identify geological structures that may influence groundwater potential, engineering suitability, and environmental conditions in the study area. The study adopted a geophysical survey approach using the ERT method, where resistivity measurements were taken along selected profiles to generate two-dimensional subsurface images. Data obtained were processed and interpreted using standard inversion software to produce resistivity models that reveal variations in lithological units. The results showed distinct subsurface layers characterized by varying resistivity values, indicating differences in soil composition, moisture content, and degree of weathering. The near-surface layer was generally composed of lateritic and sandy materials with relatively high resistivity values, while deeper zones exhibited lower resistivity indicative of clayey formations and possible water-bearing zones. The study also identified potential fracture zones and areas of structural weakness, which are important for groundwater accumulation and civil engineering planning. The study concludes that Electrical Resistivity Tomography is an effective non-invasive geophysical tool for subsurface investigation in Ugbogiobo. It provides reliable information on lithological variations and groundwater potential. The research recommends the integration of ERT surveys in site investigation studies before construction and borehole drilling to improve decision-making, reduce failure rates, and enhance sustainable groundwater development in the area.

2-D survey of a part of Ugbogiobo community and its environs has been carried out successfully and this research has helped in providing information about the subsurface of the study area. This information is of utmost importance as it gives the necessary constituents of the profile of the study area. The subsurface of a study area is related to various geological parameters such as mineral and fluid content, porosity and degree of water saturation in the rock. Major resistivity structures were delineated in both profile which is seen to be generally characterized by moderate resistivity values, at the top layers we can inferred from the low resistivity that is characterize by Clayey and Alluvium soil having a resistivity range between 200 Ωm– 800 Ωm profile 7 and 8 respectively. The major mineral occurrence in profile 7 and 8 are majorly compose of sedimentary Rocks ranging from Limestone, Shale and Sandstone with a resistivity range for Limestone between 2000 Ωm– 3000 Ωm, Shale with a resistivity range 3200 Ωm– 4000 Ωm Sandstone between resistivity range 4000 Ωm– 5000 Ωm, it will be noticed from the profiled line that all inferred mineral types fall between a depth of 2 m to 39 m. which form the lithological mineral occurrence of the both profiles. The development of two dimensional inversion resistivity algorithms has aided the processing and interpretation of complex data. Due to the inferred rock types and mineral occurences (Alluvium, Clayey soil, limestone, sandstone, and clay) gotten from the lithological interpretation of the 2-D data inversion, it can be concluded that the lithology of the study area is good for engineering purpose and construction work.

Radon is an odourless, invisible, radioactive gas naturally released from rocks, soils and water. Radon can get into homes and buildings through small cracks or holes and build up in the air. Over time, breathing in high levels of radon can cause lung cancer. Radon-222 is a naturally occurring radioactive gas that accounts for approximately half of the human annual background radiation exposure globally. Chronic exposure to radon and its decay products is estimated to be the second leading cause of lung cancer behind smoking (WHO, 2009; UNSCEAR 2000). Ionizing radiation emitted as a result of much energy from radon and its progeny can induce variety of cytogenetic effects that can be biologically damaging and results in an increased risk of carcinogenesis (The process in which normal cell are transformed into cancer cell). Suggested effects of alpha particle emission from Radon include mutation, chromosome aberrations, generation of reactive oxygen species, modification of cell cycle, up or down regulation of cytokines and the increased production of proteins associated with cell- cycle regulation and the transformation of normal cell into cancer cells. The Environmental Protection Agency recommends 148 Bq/m3 as the action level. On the other hand, International Commission for Radiation Protection (ICRP) recommends 200 Bq/m3 as the action level, while WHO recommended 100Bq/m3 as action level. The main objective of this study is focuse on how radon is established as a health hazard, its effects on cellular metabolism and energy production, and the potential of radon as a therapeutic agent for metabolism disorder, way of radon detection and measurements, methods of reducing and controlling high indoor radon concentration, and what are the recommended international action levels of radon concentrations. It mainly focuses on the health perspective of radon studies because it is a crucial and hot issue in the world today. In most developing countries like Nigeria, radon studies are not well investigated and the high mortality rate of lung cancer is of the increase.

This study examines the structural, mechanical, optical, and electronic properties of sodium niobate (NaNbO₃) perovskite using first-principles calculations within Density Functional Theory (DFT). The Generalized Gradient Approximation (GGA) and pseudopotentials in Quantum ESPRESSO were used for all computations. The optimized lattice parameters confirmed that NaNbO₃ crystallizes in an orthorhombic structure with space group Pbnm. The calculated elastic constants and related moduli met Born’s criteria for mechanical stability. The Pugh and Poisson ratios show that the compound is near the brittle–ductile boundary. Band structure results indicate an indirect band gap of about 0.4 eV, with the valence band maximum at the Γ point and the conduction band minimum at the X point. The density of states revealed strong interaction between Nb-4d and O-2p orbitals, confirming covalent bonding within the Nb–O octahedra. These findings show that NaNbO₃ is a stable indirect semiconductor with potential use in optoelectronic and photovoltaic devices.

In my work the mechanical, structural, vibration, and electronic properties of knbo3 perovskite using density functional theory (DFT). the aim of this research is to provide understanding of its characteristics and potential applications in felToelectlic devices.
In agreement with previously published theoretical values, Phonon dispersion analysis was conducted to assess the dynamical stability and vibrational behaviour of the crystal. In addition, the electronic band structure and density of states (DOS) were anaIyzed to understand the nature of its bonding and band gap. This work gave explanation to the computational techniques used and offer a rigid understanding of the structural, mechanical, and electrical properties of K
Nb03 perovskite.