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Pressure-Driven Valence Increase and Metallization in Kondo Insulator Ce$_3$Bi$_4$Pt$_3$

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 نشر من قبل Daniel J. Campbell
 تاريخ النشر 2019
  مجال البحث فيزياء
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We report the results of high pressure x-ray diffraction, x-ray absorption, and electrical transport measurements of Kondo insulator Ce$_3$Bi$_4$Pt$_3$ up to 42 GPa, the highest pressure reached in the study of any Ce-based KI. We observe a smooth decrease in volume and movement toward intermediate Ce valence with pressure, both of which point to increased electron correlations. Despite this, temperature-dependent resistance data show the suppression of the interaction-driven ambient pressure insulating ground state. We also discuss potential ramifications of these results for the predicted topological KI state.



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