| dc.description.abstract | Nanoscale superconducting materials have garnered significant attention because they have the potential to develop new and enhanced properties for technological applications. High critical temperature superconductors (Tc) made from transition and lanthanide oxides are particularly promising due to their capability to produce strong currents in magnetic fields. Notably, research has shown that particle size plays a crucial role in enhancing the critical current density in these materials. Perovskite materials have attracted research because of their ability to transition from normal metals to superconductors. They are attractive for a wide range of applications due to their unique characteristics and properties, such as light-emitting diodes, power transmission cables, photovoltaic, and pressure-induced emission. Electronic structure and dynamical properties are key in understanding the behaviour of materials in relation to stability for superconductivity.Both theoretical and experimental approaches have been employed to make new discoveries in these endeavours. This research explored the electronic structure in depth, uncovering essential aspects like bandgaps and Fermi surfaces, as well as offering valuable insights into the material's behaviour. Furthermore, the dynamical properties through investigation of phonon spectra and lattice dynamics to analyse vibrational modes and their impacts on material stability and functionality have been studied.Superconducting properties of LaBa2Cu3O7 have also been studied through analysis of critical temperature and superconducting gap through first-principles computation. The main objective of this research was to study externally applied pressure doping, phase transition behaviour, and superconducting properties of LaBa2Cu3O7 using ab initio approach. The ground state energy was calculated within the framework of density functional theory (DFT), utilizing the plane wave self-consistent field (PWscf) and ultra-soft pseudopotential (USPP) method. This calculation was performed using the Perdew-Burke Ernzerhof (PBE) generalized gradient approximation and local density approximations, as implemented in the Quantum Espresso Code.Under electronic structure, the results showed that LaBa2Cu3O7 is an orthorhombic structure with a band gap of 2.043 eV,indicating it’s a semiconductor. However, under pressure, it becomes a superconductor, thus metallic. LaBa2Cu3O7 is dynamically stable, as there were no negative frequencies obtained on the phonon dispersion curve. When pressure was induced, it indicated that a pressure of 20 GPa resulted in the highest Tc. From pressure-induced doping, it was confirmed that pressure can induce doping, thereby enhancing the superconductivity transition temperature up to the optimal doping level. The optimal superconductivity transition temperature was found to be higher than the normal transition temperature. | en_US |
