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Trivial topological phase of CaAgP and the topological nodal-line transition in CaAg(P1-xAsx)

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 نشر من قبل Nan Xu
 تاريخ النشر 2018
  مجال البحث فيزياء
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By performing angle-resolved photoemission spectroscopy and first-principles calculations, we address the topological phase of CaAgP and investigate the topological phase transition in CaAg(P1-xAsx). We reveal that in CaAgP, the bulk band gap and surface states with a large bandwidth are topologically trivial, in agreement with hybrid density functional theory calculations. The calculations also indicate that application of negative hydrostatic pressure can transform trivial semiconducting CaAgP into an ideal topological nodal-line semimetal phase. The topological transition can be realized by partial isovalent P/As substitution at x = 0.38.

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