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arXiv · 0809.4702

High pressure study on LaFeAsO with different Tc

Wei Yi·Chao Zhang·Liling Sun·Zhi-an Ren·Wei Lu·Xiaoli Dong·Zhengcai Li·Guangcan Che·Jie Yang·Xiaoli Shen·Xi Dai·Zhong Fang·Fang Zhou·Zhongxian Zhao
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Abstract

We report studies on pressure dependence of superconducting transition temperature (Tc) of LaFeAsO, LaFeAs(O0.5F0.5) and LaFeAs(O0.89F0.11) samples. In-situ resistance measurements under high pressure showed that the Tc of these three compounds increases with pressure initially, reaches a maximum value and then decreases with further increasing pressure, although the Tc at ambient pressure are different. The onset Tc of LaFeAsO is ~50 K at 1.5 GPa, which is the highest record in La-based oxypnicited system. The significant change in Tc induced by pressure is attributed to the orbital degeneracy and the electron density of state at the Fermi level.

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Wei Yi, Chao Zhang, Liling Sun, Zhi-an Ren, Wei Lu, Xiaoli Dong, Zhengcai Li, Guangcan Che, Jie Yang, Xiaoli Shen, Xi Dai, Zhong Fang, Fang Zhou, Zhongxian Zhao. 2008-09-28. High pressure study on LaFeAsO with different Tc. https://doi.org/10.1209/0295-5075/84/67009

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