Tailoring electronic and optical properties of Lutetium pyrosilicate (Lu2Si2O7) through Nd and Tb doping: Insights from DFT plus U plus U calculations

In this research paper, we investigate the electronic and optical properties of Lutetium pyrosilicate (Lu2Si2O7, LPS) by Nd and Tb doping using density functional theory (DFT) calculations within the framework of the WIEN2k code. The DFT + U method is employed to account for the strong correlation effects in the rare earth dopants. The analysis of the electronic properties reveals that the materials under investigation exhibit semiconductor behavior. The calculated spin up/dn energy band gaps for pristine, Nd & Tb doping Lu2Si2O7 are determined to be 4.610/4.660 eV, 4.635/5.162 eV, and 5.06/4.45 eV, respectively. Our results reveal that the doping of Nd and Tb impurities leads to the introduction of new electronic states within the band gap of Lu2Si2O7, resulting in a significant modification of the electronic and optical properties. Specifically, we find that the Tb-doped Lu2Si2O7 shows a wide band gap and enhanced optical absorption in the visible region, while the Nd-doped Lu2Si2O7 exhibits a broadened band gap and reduced optical absorption in the visible region. This study can provide a reference for future research and helps to extend the properties of Lu2Si2O7 by Nd and Tb materials into the optical applications.