Quantum Spin Hall Insulator State in HgTe Quantum Wells

  title={Quantum Spin Hall Insulator State in HgTe Quantum Wells},
  author={Markus K{\"o}nig and Steffen Wiedmann and Christoph Br{\"u}ne and Andreas Roth and Hartmut Buhmann and Laurens W. Molenkamp and Xiao-liang Qi and Shou-Cheng Zhang},
  pages={766 - 770}
Recent theory predicted that the quantum spin Hall effect, a fundamentally new quantum state of matter that exists at zero external magnetic field, may be realized in HgTe/(Hg,Cd)Te quantum wells. We fabricated such sample structures with low density and high mobility in which we could tune, through an external gate voltage, the carrier conduction from n-type to p-type, passing through an insulating regime. For thin quantum wells with well width d < 6.3 nanometers, the insulating regime showed… 
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