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arXiv · 1005.3089

Upper critical field and de Haas-van Alphen oscillations in KOs$_2$O$_6$ measured in a hybrid magnet

Taichi Terashima·Nobuyuki Kurita·Atsushi Harada·Kota Kodama·Jun-ichi Yamaura·Zenji Hiroi·Hisatomo Harima·Shinya Uji
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Abstract

Magnetic torque measurements have been performed on a KOs$_2$O$_6$ single crystal in magnetic fields up to 35.3 T and at temperatures down to 0.6 K. The upper critical field is determined to be $\sim$30 T. De Haas-van Alphen oscillations are observed. A large mass enhancement of (1+$λ$) = $m^* / m_{band}$ = 7.6 is found. It is suggested that, for the large upper critical field to be reconciled with Pauli paramagnetic limiting, the observed mass enhancement must be of electron-phonon origin for the most part.

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Taichi Terashima, Nobuyuki Kurita, Atsushi Harada, Kota Kodama, Jun-ichi Yamaura, Zenji Hiroi, Hisatomo Harima, Shinya Uji. 2010-07-27. Upper critical field and de Haas-van Alphen oscillations in KOs$_2$O$_6$ measured in a hybrid magnet. https://doi.org/10.1143/jpsj.79.083703

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