Direct observations of the band alignment of LaAlO3/SrTiO3 using scanning tunneling microscopy

ORAL

Abstract

In this work, by using cross-sectional scanning tunneling microscopy, local and direct evidence of the electronic information across the LaAlO3/SrTiO3 hetero-interfaces are investigated. A combination of scanning tunneling spectroscopy and analysis with atomic resolution across the hetero-interface reveals how the oppositely charged atomic planes undergo electronic reconstructions and introduce a built-in electric field across the polar LaAlO3 thin films grown on SrTiO3 substrates. With the consideration of the tip-induced band bending effect, the magnitude of the built-in field across LaAlO3, the band bending on SrTiO3 side, and the decay length of the band downshift of SrTiO3 side at the hetero-interface are directly observed.

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Authors

  • Y.P. Chiu

    • Department of Physics, National Sun Yat-sen University, Kaohsiung, 804, Taiwan

  • B.C. Huang

    • Department of Physics, National Sun Yat-sen University, Kaohsiung, 804, Taiwan

  • P.C. Huang

    • Department of Physics, National Sun Yat-sen University, Kaohsiung, 804, Taiwan

  • V.T. Tra

    • Institute of Physics, National Chiao Tung University, Hsinchu, 300, Taiwan

  • J.Y. Lin

    • Institute of Physics, National Chiao Tung University, Hsinchu, 300, Taiwan

  • J.C. Yang

    • Department of Materials Science and Engineering, National Chiao Tung University, HsinChu, 300, Taiwan

  • Y.H. Chu

    • Department of Materials Science and Engineering, National Chiao Tung University, HsinChu, 300, Taiwan