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arXiv · 1707.03535

Influence of growth flux solvent on anneal-tuning of ground states in CaFe2As2

Connor Roncaioli·Tyler Drye·Shanta Saha·Johnpierre Paglione
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Abstract

The effects of anneal-tuning of single-crystalline samples of CaFe$_2$As$_2$ synthesized via a molten Sn flux method are investigated using x-ray diffraction, chemical composition, electrical transport and magnetic susceptibility measurements in order to understand the role of growth conditions on the resultant phase diagram. Previous studies of CaFe$_2$As$_2$ crystals synthesized using a self-flux (FeAs) method revealed an ability to tune the structural and magnetic properties of this system by control of post-synthesis annealing conditions, resulting in an ambient pressure phase diagram that spans from tetragonal/orthorhombic antiferromagnetism to the collapsed tetragonal phase of this system. In this work, we compare previous results to those obtained on crystals synthesized via Sn flux, finding similar tunability in both self- and Sn-flux cases, but less sensitivity to annealing temperatures in the latter case, resulting in a temperature-shifted phase diagram.

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Connor Roncaioli, Tyler Drye, Shanta Saha, Johnpierre Paglione. 2017-07-12. Influence of growth flux solvent on anneal-tuning of ground states in CaFe2As2. https://doi.org/10.1103/physrevmaterials.2.044801

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