Imaging of Coulomb-driven quantum Hall edge states.

  title={Imaging of Coulomb-driven quantum Hall edge states.},
  author={Keji Lai and Worasom Kundhikanjana and Michael A. Kelly and Zhi-Xun Shen and Javad Shabani and Mansour Shayegan},
  journal={Physical review letters},
  volume={107 17},
The edges of a two-dimensional electron gas (2DEG) in the quantum Hall effect (QHE) regime are divided into alternating metallic and insulating strips, with their widths determined by the energy gaps of the QHE states and the electrostatic Coulomb interaction. Local probing of these submicrometer features, however, is challenging due to the buried 2DEG structures. Using a newly developed microwave impedance microscope, we demonstrate the real-space conductivity mapping of the edge and bulk… 
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