Journal of Materials Science

, Volume 50, Issue 1, pp 74–78 | Cite as

Two-dimensional electron gas in the KNbO3:Y ultrathin film

  • Yanqing Shen
  • Wenhan Wang
  • Zhongxiang Zhou
  • Yongyuan Jiang
  • Chunfeng Hou
  • Weidong Fei
Original Paper


First-principles calculations are used to study KNbO3:Y ultrathin film. The conducting two-dimensional electron gas (2DEG) is found in KNbO3:Y film, whereas SrTiO3:Y superlattice is insulating [Science 331, 886 (2011)]. The carrier density of 2DEG of KNbO3:Y film is twice that of LaTiO3/SrTiO3 superlattice, which is in agreement with the theoretical results of KNbO3:La superlattice. It is found that the charge densities of different monolayers are modulated by the polarization effect of KNbO3. We predict that 2DEG may be in other rare-earth atoms-doped KNbO3 film.


Ultrathin Film Ferroelectric Polarization Fermi Energy Level KNbO3 Parabolic Energy Band 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The research is supported by National Natural Science Foundation of China (Nos.11204053 and 11074059) and the China Postdoctoral Science Foundation (Grant No. 2013M531028). We would like to thank High Performance Computing Center of Harbin Institute of Technology for the help of the calculation.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Yanqing Shen
    • 1
    • 2
  • Wenhan Wang
    • 1
  • Zhongxiang Zhou
    • 1
  • Yongyuan Jiang
    • 1
  • Chunfeng Hou
    • 1
  • Weidong Fei
    • 2
  1. 1.Department of PhysicsHarbin Institute of TechnologyHarbinPeople’s Republic of China
  2. 2.School of Materials Science and EngineeringHarbin Institute of TechnologyHarbinPeople’s Republic of China

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