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Topological frequency shift of quantum oscillation in CaFeAsF

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 نشر من قبل Taichi Terashima
 تاريخ النشر 2021
  مجال البحث فيزياء
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Shubnikov-de Haas oscillation measurements were performed on CaFeAsF up to a high temperature of $T$ = 7 K. The oscillation frequency of the $alpha$ Dirac electron cylinder exhibits a $T^2$ shift as the temperature is raised, while that of the $beta$ Schrodinger hole cylinder shows no clear shift. The observed shift is reasonably explained by the topological frequency shift proposed in [Guo, Alexandradinata, textit{et al.}, arXiv:1910.07608] which argues that the energy dependence of the effective mass peculiar to a linear band dispersion gives rise to a frequency shift proportional to $T^2$. The present result corroborate the applicability of the topological frequency shift to distinguish topologically nontrivial pockets from trivial ones.



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