Superconductivity at 31×3 K in Yb-doped La(O/F)FeAs superconductors

Prakash, J. ; Singh, S. J. ; Patnaik, S. ; Ganguli, A. K. (2010) Superconductivity at 31×3 K in Yb-doped La(O/F)FeAs superconductors Journal of Chemical Sciences, 122 (1). pp. 43-46. ISSN 0377-8444

PDF - Publisher Version

Official URL:

Related URL:


The effect of ytterbium substitution at the lanthanum site on the superconducting properties of La1−x Yb x O0·8F0·2FeAs (x = 0·10, 0·20 and 0·30) oxypnictides has been investigated. Powder X-ray diffraction studies show the presence of Yb2O3 and LaOF as secondary phases. The superconducting transition temperature (T c ) of 31·3 (± 0·05) K has been observed in x = 0·1 composition which is the maximum T c so far in the La(O/F)FeAs superconductor family at ambient pressure. Further increase in x leads to suppression and broadening of superconducting transition. The resistive transition curves under different magnetic fields were investigated, leading to determination of upper critical field H c2 (T) of this new superconductor. The value of H c2 at zero temperature is estimated to be about 46 T corresponding to coherence length ~27 Å.

Item Type:Article
Source:Copyright of this article belongs to Indian Academy of Sciences.
Keywords:Oxypnictides; Superconductivity; Upper Critical Field
ID Code:62030
Deposited On:16 Sep 2011 03:58
Last Modified:18 May 2016 11:29

Repository Staff Only: item control page