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

Nobuyuki Kurita; Motoi Kimata; Kota Kodama; Atsushi Harada; Megumi Tomita; Hiroyuki S. Suzuki; Takehiko Matsumoto; Keizo Murata; Shinya Uji; Taichi Terashima

doi:10.1103/physrevb.88.224510

arXiv · 1312.3380

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

Nobuyuki Kurita·Motoi Kimata·Kota Kodama·Atsushi Harada·Megumi Tomita·Hiroyuki S. Suzuki·Takehiko Matsumoto·Keizo Murata·Shinya Uji·Taichi Terashima

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Abstract

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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Nobuyuki Kurita, Motoi Kimata, Kota Kodama, Atsushi Harada, Megumi Tomita, Hiroyuki S. Suzuki, Takehiko Matsumoto, Keizo Murata, Shinya Uji, Taichi Terashima. 2013-12-12. Pressure-induced superconductivity in EuFe2As2 without a quantum critical point: magnetotransport and upper critical field measurements under high pressure. https://doi.org/10.1103/physrevb.88.224510

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