Artigo Acesso aberto

Narrow superconducting window in LaFe 1 − x Ni x AsO

2009; American Physical Society; Volume: 79; Issue: 17 Linguagem: Inglês

10.1103/physrevb.79.174505

ISSN

1550-235X

Autores

Guang‐Han Cao, Shuai Jiang, Xiao Lin, Cao Wang, Yuke Li, Zhi Ren, Tao Qian, Chunmu Feng, Jianhui Dai, Zhu‐An Xu, Fu‐Chun Zhang,

Tópico(s)

Corporate Taxation and Avoidance

Resumo

We have studied Ni-substitution effect in ${\text{LaFe}}_{1\ensuremath{-}x}{\text{Ni}}_{x}\text{AsO}$ $(0\ensuremath{\le}x\ensuremath{\le}0.1)$ by the measurements of x-ray diffraction, electrical resistivity, magnetic susceptibility, and heat capacity. The nickel doping drastically suppresses the resistivity anomaly associated with spin-density-wave ordering in the parent compound. Superconductivity emerges in a narrow region of $0.03\ensuremath{\le}x\ensuremath{\le}0.06$ with the maximum ${T}_{c}$ of 6.5 K at $x=0.04$, where enhanced magnetic susceptibility shows up. The upper critical field at zero temperature is estimated to exceed the Pauli paramagnetic limit. The much lowered ${T}_{c}$ in comparison with ${\text{LaFeAsO}}_{1\ensuremath{-}x}{\text{F}}_{x}$ system is discussed.

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