Abstract
The Ca 1-xSr xFe 2As 2 (0 ≤ x ≤ 1) and Ca 0.5Sr 0.5 Fe 2-yCo yAs 2 (0 ≤ y ≤ 0.6) materials were prepared by a solid state reaction method. X-ray diffraction analysis shows that the lattice parameters of Ca 1-xSr xFe 2As 2 decrease continuously with increasing Ca content. Resistivity measurements reveal that the Ca/Sr ratio has a visible influence on the resistivity anomaly associated with the spin-density-wave (SDW) instability. Experimental measurements on Ca 0.5Sr 0.5Fe 2-yCo yAs 2 show clear superconducting transitions for Co in range of 0.26 ≤ y ≤ 0.43; the highest critical transition temperature is found to be at about 17 K. Transmission electron microscopy (TEM) investigations on the superconducting Ca 0.5Sr 0.5Fe 2-yCo yAs 2 samples reveal visible inhomogeneous distribution of Sr and Ca elements, which could result in structural distortions and broaden superconducting transitions as observed in our experiments.
| Original language | English |
|---|---|
| Pages (from-to) | 749-755 |
| Number of pages | 7 |
| Journal | Journal of Superconductivity and Novel Magnetism |
| Volume | 23 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - Jul 2010 |
| Externally published | Yes |
Keywords
- SDW
- Structural inhomogeneity
- Superconductivity