Neerav Kharche

Valley degeneracies in (111) Si quantum wells

Valley degeneracies in (111) Si quantum wells Neerav Kharche, Seongmin Kim, Timothy Boykin, Gerhard Klimeck


  • Resolve discrepancies in experimentally observed and theoretically predicted valley degeneracies
  • Study effect of surface morphology on the electronic structure


  • Supercell tight-binding calculations to model surface miscuts
  • Effective mass based valley-projection model to determine the directions of valley-minima of large supercells


  • Atomistic basis representation is essential to capture the effect of mono-atomic steps on the electronic structure
  • Surface miscut of (111) Si is found to be the origin of breaking of 6 fold valley degeneracy into lower 2 fold and higher 4 fold valley degeneracies


  • Flat (111) Si QW shows 6 fold valley degeneracy
  • Miscut causes 2-4 splitting due to different effective masses in confinement direction

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