Structural and Electronic Properties of Ag-Doped in Ba-Site of YBa2-xAgxCu3Oδ Using Density Functional Theory via First Principle Study

Abstract

This study reports on the First Principle Study via Density Functional Theory (DFT) used to determine the structural and electronic properties of Ag-dopant in Ba-site of YBa2-xAgxCu3Oδ superconductor. The computational method adopting CASTEP computational code was used to calculate the structural and electronic properties for Ag-dopant in range of x=0.150 to x=0.250 in Ba-site of YBa2-xAgxCu3Oδ to enhance the performance finding of experimental work shown at dopant x=0.20 ceramic superconductor. The structural changes in terms of lattice parameters were compared as the percentage of dopant increases to seek both CuO chain and CuO2 plane bond length and the spontaneous strain variance on the structure orthorhombicity. The crystal structure constructed and calculated using Visual Crystal Approximation (VCA) applying the local density approximation (LDA) and ultrasoft pseuodopotential. Geometry optimization shown energy converged at 400 eV with k-point sampling of 4x4x1. The structural properties of YBa2-xAgxCu3Oδ are observed to be approximately close to the experimental data obtained by other researches. The electronic properties were determined via energy band gap, density of states and electron energy differences visualisation a to further enhance the experimental findings.