arXiv 0909.46002009-09-25cond-mat.supr-concond-mat.str-el

Structural properties and superconductivity of SrFe2As2-xPx and CaFe2As2-yPy

H. L. Shi, H. X. Yang, H. F. Tian, J. B. Lu, Z. W. Wang, Y. B. Qin, Y. J. Song, J. Q. Li*

备注：: 11 pages, 5 figures, 2 tables
DOI：: 10.1088/0953-8984/22/12/125702

英文摘要：

The SrFe2As2-xPx and CaFe2As2-yPy materials were prepared by a solid state reaction method. X-ray diffraction measurements indicate the single-phase samples can be successfully obtained for SrFe2As2-xPx and CaFe2As2-yPy samples. Clear contraction of the lattice parameters are clearly determined due to the relatively smaller P ions substation for As. The SDW instability associated with tetragonal to orthorhombic phase transition is suppressed visibly in both systems following with the increase of P contents. The highest superconducting transitions are respectively observed at about 27 K in SrFe2As1.3P0.7 and at about 13 K in CaFe2As1.7P0.3.

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