Evidence for helical edge modes in inverted InAs/GaSb quantum wells.

  title={Evidence for helical edge modes in inverted InAs/GaSb quantum wells.},
  author={Ivan Knez and Rui-Rui Du and Gerard J. Sullivan},
  journal={Physical review letters},
  volume={107 13},
We present an experimental study of low temperature electronic transport in the hybridization gap of inverted InAs/GaSb composite quantum wells. An electrostatic gate is used to push the Fermi level into the gap regime, where the conductance as a function of sample length and width is measured. Our analysis shows strong evidence for the existence of helical edge modes proposed by Liu et al [Phys. Rev. Lett. 100, 236601 (2008)]. Edge modes persist in spite of sizable bulk conduction and show… Expand
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