Abstract
This paper focuses on the atomic and electronic structure of the interesting thermoelectric superlattices , SrTiO3/Nb doped SrTiO3/SrTiO3 and SrTiO3/Nb doped SrTiO3/BaTiO3 superlattices. They were fabricated on the (001) LaAlO3 substrate by pulsed laser deposition (PLD) method. Z-contrast HAADF image and ELNES were taken by STEM equipped with a spherical aberration-corrector and parallel electron energy loss spectrometer. The electronic structure and ELNES of the superlattice were calculated by using a first principles PAW method and a first principles relativistic multi-electron method. It was found that Nb preferentially solve to Ti site, and Ti in the Nb doped layer have extra electron, and it causes the 2DEG formation. Details on the STEM-ELNS and first principles calculations will be present.
