Anomalously large measured thermoelectric power factor in Sr1−xLaxTiO3 thin films due to SrTiO3 substrate reduction

  title={Anomalously large measured thermoelectric power factor in Sr1−xLaxTiO3 thin films due to SrTiO3 substrate reduction},
  author={Matthew L. Scullin and Choongho Yu and Mark Huijben and Subroto Mukerjee and Jan Seidel and Qian Zhan and Joel E Moore and A. Majumdar and Rocketdyne Division and Lawrence Hall of Science and Engineering and University of Southern California and Berkeley Department of Mechanical Engineering and Texas AM University Department of Mechanical Engineering and Berkeley Department of Physics and Berkeley},
  journal={Applied Physics Letters},
We report the observation that thermoelectric thin films of La-doped SrTiO3 grown on SrTiO3 substrates yield anomalously high values of thermopower to give extraordinary values of power factor at 300 K. Thin films of Sr0.98La0.02TiO3, grown via pulsed laser deposition at low temperature and low pressure (450 °C, 10−7 Torr), do not yield similarly high values when grown on other substrates. The thin-film growth induces oxygen reduction in the SrTiO3 crystals, doping the substrate n type. It is… 
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