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Nontrivial Berry phase and type II Dirac transport in layered material PdTe2

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 نشر من قبل Fengqi Song
 تاريخ النشر 2016
  مجال البحث فيزياء
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Here we report the evidence of the type II Dirac Fermion in the layered crystal PdTe2. The de Haas-van Alphen oscillations find a small Fermi pocket with a cross section of 0.077nm-2 with a nontrivial Berry phase. First-principal calculations reveal that it is originated from the hole pocket of a tilted Dirac cone. Angle Resolved Photoemission Spectroscopy demonstrates a type II Dirac cone featured dispersion. We also suggest PdTe2 is an improved platform to host the topological superconductors.

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