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Pressure-induced superconductivity in EuFe2As2 without a quantum critical point: magnetotransport and upper critical field measurements under high pressure

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 نشر من قبل Nobuyuki Kurita
 تاريخ النشر 2013
  مجال البحث فيزياء
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Resistivity and Hall effect measurements of EuFe$_2$As$_2$ up to 3.2,GPa indicate no divergence of quasiparticle effective mass at the pressure $P_mathrm{c}$ where the magnetic and structural transition disappears. This is corroborated by analysis of the temperature ($T$) dependence of the upper critical field. $T$-linear resistivity is observed at pressures slightly above $P_mathrm{c}$. The scattering rates for both electrons and holes are shown to be approximately $T$-linear. When a field is applied, a $T^2$ dependence is recovered, indicating that the origin of the $T$-linear dependence is spin fluctuations.



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