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arXiv · 0907.4212

Evidence for Competition between Superconductivity and Kondo Effect in CeFeAsO0.7F0.3 under High Pressure

Liling Sun·Xi Dai·Chao Zhang·Wei Yi·enfu Cheng·Nanlin Wang·Lirong Zheng·Zheng Jiang·Xiangjun Wei·Yuying Huang·Jie Yang·Zhian Ren·Wei Lu·Xiaoli Dong·Guangcan Che·Qi Wu·Hong Ding·Jing Liu·Tiandou Hu·Zhongxian Zhao
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Abstract

We discover a pressure induced quantum phase transition from the superconducting state to the non-superconducting Kondo screened phase associated with a 2% volume collapse in CeFeAsO0.7F0.3 through measurements of high-pressure resistance, synchrotron x-ray diffraction, and x-ray absorption spectroscopy (XAS) in a diamond anvil cell. Our XAS data of Ce-L3 in CeFeAsO0.7F0.3 clearly show a spectral weight transfer from the main line to the satellite line after the transition, demonstrating the formation of the Kondo singlets under pressure in CeFeAsO1-xFx. Our results have revealed a physical picture of a pressure-induce competition between Kondo singlets and BCS singlets in the Ce-pnictide superconductors.

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Liling Sun, Xi Dai, Chao Zhang, Wei Yi, enfu Cheng, Nanlin Wang, Lirong Zheng, Zheng Jiang, Xiangjun Wei, Yuying Huang, Jie Yang, Zhian Ren, Wei Lu, Xiaoli Dong, Guangcan Che, Qi Wu, Hong Ding, Jing Liu, Tiandou Hu, Zhongxian Zhao. 2010-09-02. Evidence for Competition between Superconductivity and Kondo Effect in CeFeAsO0.7F0.3 under High Pressure. https://doi.org/10.1209/0295-5075%2F91%2F57008

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