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Suppression of Nonmagnetic Insulating State by Application of Pressure in Mineral Tetrahedrite Cu$_{12}$Sb$_{4}$S$_{13}$

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 نشر من قبل Shunsaku Kitagawa
 تاريخ النشر 2015
  مجال البحث فيزياء
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The mineral tetrahedrite Cu$_{12}$Sb$_{4}$S$_{13}$ exhibits a first-order metal--insulator transition (MIT) at $T_{rm MI}$ = 85 K and ambient pressure. We measured the $^{63}$Cu-NMR at ambient pressure and the resistivity and magnetic susceptibility at high pressures. $^{63}$Cu-NMR results indicate a nonmagnetic insulating ground state in this compound. The MIT is monotonically suppressed by pressure and disappears at $sim1.0$ GPa. Two other anomalies are observed in the resistivity measurements, and the pressure -- temperature phase diagram of Cu$_{12}$Sb$_{4}$S$_{13}$ is constructed.



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