Thermal expansion of CaFe2As2: Effect of cobalt doping and postgrowth thermal treatment

TitleThermal expansion of CaFe2As2: Effect of cobalt doping and postgrowth thermal treatment
Publication TypeJournal Article
Year of Publication2013
AuthorsBud'ko SL, Ran S, Canfield PC
Journal TitlePhysical Review B
Volume88
Pages064513
Date Published08
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberWOS:000323572900015
Keywordsbafe2as2, superconductivity
Abstract

We report thermal expansion measurements on Ca(Fe1-xCox)(2)As-2 single crystals with different thermal treatment, with samples chosen to represent four different ground states observed in this family. For all samples, thermal expansion is anisotropic with different signs of the in-plane and c-axis thermal expansion coefficients in the high temperature, tetragonal phase. The features in thermal expansion associated with the phase transitions are of opposite signs as well, pointing to a different response of transition temperatures to the in-plane and the c-axis stress. These features, and consequently the inferred pressure derivatives, are very large, clearly and substantially exceeding those in the Ba(Fe1-xCox)(2)As-2 family. For all transitions the c-axis response is dominant.

URL<Go to ISI>://WOS:000323572900015
DOI10.1103/PhysRevB.88.064513