Optical and electronic spectra in a transparent transition metal oxide from first-principles quasiparticle self-consistent calculations
Phys. Rev. B 113, 155114 – Published 6 April, 2026
DOI: https://doi.org/10.1103/hsmv-pgd7
Abstract
For the transparent transition-metal oxide (LTO), optical and electronic spectra were investigated using a nonempirical computational approach, the quasiparticle self-consistent GW method (QSGW). The converged one-particle Hamiltonian determined the band dispersion curves, which exhibited a narrower bandwidth and an increased density of states at the Fermi level due to electron localization effects, compared to results obtained with density functional theory. The dielectric function obtained via QSGW revealed that pseudoplasmons arising from interband optical transitions appear in the infrared frequency range, providing a full explanation for the transparency of LTO. By evaluating the self-energy of the hole quasiparticles, the properties of plasmonic polarons were investigated across the Brillouin zone using the cumulant approach under the QSGW framework. Their energy spectra, including plasmon satellites, were discussed in comparison with available experimental photoemission spectroscopy data.
