Electronic structure of BaSnO3 investigated by high-energy-resolution electron energy-loss spectroscopy and ab initio calculations

摘要

There has been growing interest in perovskite BaSnO3 due to its desirableproperties for oxide electronic devices including high electron mobility atroom temperature and optical transparency. As these electronic and opticalproperties originate largely from the electronic structure of the material,here the basic electronic structure of epitaxially-grown BaSnO3 films isstudied using high-energy-resolution electron energy-loss spectroscopy in atransmission electron microscope and ab initio calculations. This studyprovides a detailed description of the dielectric function of BaSnO3, includingthe energies of bulk plasmon excitations and critical interband electronictransitions, the band structure and partial densities of states, the measuredband gap, and more. To make the study representative of a variety of depositionmethods, results from BaSnO3 films grown by both hybrid molecular beam epitaxyand high pressure oxygen sputter deposition are reported.