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arXiv · 0909.1937

Magnetic and Superconducting Properties of FeAs-based High-Tc Superconductors with Gd

E. P. Khlybov·O. E. Omelyanovsky·A. Zaleski·A. V. Sadakov·D. R. Gizatulin·L. F. Kulikova·I. E. Kostyleva·V. M. Pudalov
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Abstract

We report on successful synthesis under high pressure of a series of polycrystalline GdFeAs O_{1-x}F_x high-Tc superconductors with different oxygen deficiency x=0.12 - 0.16 and also with no fluorine. We have found that the high-pressure synthesis technique is crucial for obtaining almost single-phase superconducting materials: by synthesizing the same compounds with no pressure in ampoules we obtained non-superconducting materials with an admixture of incidental phases. Critical temperature for all the materials was in the range 40 to 53K. The temperature derivative of the critical field dHc2/dT is remarkably high, indicating potentially high value of the second critical field Hc2 ~ 130T.

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E. P. Khlybov, O. E. Omelyanovsky, A. Zaleski, A. V. Sadakov, D. R. Gizatulin, L. F. Kulikova, I. E. Kostyleva, V. M. Pudalov. 2009-09-10. Magnetic and Superconducting Properties of FeAs-based High-Tc Superconductors with Gd. https://doi.org/10.1134/s0021364009170159

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