Quantum Hall Effect in Polar Oxide Heterostructures

  title={Quantum Hall Effect in Polar Oxide Heterostructures},
  author={A. Tsukazaki and A. Ohtomo and T. Kita and Y. Ohno and H. Ohno and M. Kawasaki},
  pages={1388 - 1391}
We observed Shubnikov–de Haas oscillation and the quantum Hall effect in a high-mobility two-dimensional electron gas in polar ZnO/MgxZn1–xO heterostructures grown by laser molecular beam epitaxy. The electron density could be controlled in a range of 0.7 × 1012 to 3.7 × 1012 per square centimeter by tuning the magnesium content in the barriers and the growth polarity. From the temperature dependence of the oscillation amplitude, the effective mass of the two-dimensional electrons was derived… Expand

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