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arXiv · 1005.3868

Comment on "Quantum Criticality and Nodal Superconductivity in the FeAs-Based Superconductor KFe$_2$As$_2$"

Taichi Terashima·Motoi Kimata·Nobuyuki Kurita·Hidetaka Satsukawa·Atsushi Harada·Kaori Hazama·Motoharu Imai·Akira Sato·Kunihiro Kihou·Chul-Ho Lee·Hijiri Kito·Hiroshi Eisaki·Akira Iyo·Taku Saito·Hideto Fukazawa·Yoh Kohori·Hisatomo Harima·Shinya Uji
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Abstract

In a recent Letter [J. K. Dong et al., Phys. Rev. Lett. 104, 087005 (2010)], Dong \textit{et al}. have observed a $T^{1.5}$ dependence of resistivity $ρ$ in KFe$_2$As$_2$ at the upper critical field $B_{c2}$ = 5 T parallel to the c axis and have suggested the existence of a field-induced quantum critical point (QCP) at $B_{c2}$. In this comment, we argue that observation of a $T^{1.5}$ dependence of $ρ$ in a sample showing broad resistive transitions does not constitute evidence for a QCP and that recent dHvA results do not support the proposed QCP.

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Taichi Terashima, Motoi Kimata, Nobuyuki Kurita, Hidetaka Satsukawa, Atsushi Harada, Kaori Hazama, Motoharu Imai, Akira Sato, Kunihiro Kihou, Chul-Ho Lee, Hijiri Kito, Hiroshi Eisaki, Akira Iyo, Taku Saito, Hideto Fukazawa, Yoh Kohori, Hisatomo Harima, Shinya Uji. 2010-05-21. Comment on "Quantum Criticality and Nodal Superconductivity in the FeAs-Based Superconductor KFe$_2$As$_2$". https://doi.org/10.1103/physrevlett.104.259701

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