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arXiv · 1303.7281

Hysteretic superconducting resistive transition in Ba0.07K0.93Fe2As2

Taichi Terashima·Kunihiro Kihou·Megumi Tomita·Satoshi Tsuchiya·Naoki Kikugawa·Shigeyuki Ishida·Chul-Ho Lee·Akira Iyo·Hiroshi Eisaki·Shinya Uji
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Abstract

We have observed hysteresis in superconducting resistive transition curves of Ba$_{0.07}$K$_{0.93}$Fe$_2$As$_2$ ($T_c\sim$8 K) below about 1 K for in-plane fields. The hysteresis is not observed as the field is tilted away from the $ab$ plane by 20$^{\circ}$ or more. The temperature and angle dependences of the upper critical field indicate a strong paramagnetic effect for in-plane fields. We suggest that the hysteresis can be attributed to a first-order superconducting transition due to the paramagnetic effect. Magnetic torque data are also shown.

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Taichi Terashima, Kunihiro Kihou, Megumi Tomita, Satoshi Tsuchiya, Naoki Kikugawa, Shigeyuki Ishida, Chul-Ho Lee, Akira Iyo, Hiroshi Eisaki, Shinya Uji. 2013-03-29. Hysteretic superconducting resistive transition in Ba0.07K0.93Fe2As2. https://doi.org/10.1103/physrevb.87.184513

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