One-step method to grow Ba0.6K0.4Fe2As2 single crystals without fluxing agent

TL;DR

This paper presents a simple, flux-free one-step method for growing high-quality Ba0.6K0.4Fe2As2 single crystals with excellent superconducting properties, potentially applicable to other Fe-based superconductors.

Contribution

A novel flux-free one-step growth technique for high-quality Ba0.6K0.4Fe2As2 single crystals with superior superconducting characteristics.

Findings

High crystalline quality and c-axis orientation confirmed by X-ray diffraction

Superconducting transition temperature up to 38 K

Large current carrying capacity and high upper critical fields

Abstract

Single crystals of Ba0.6K0.4Fe2As2 with excellent quality have been successfully grown without fluxing agent through a simple one-step method for the first time. X-ray diffraction patterns demonstrate that the samples have high crystalline quality and c-axis orientation. The onset transition temperature is up to 38 K with the zero resistivity temperature about 36.7 K. Both the R-T and M-T data show a very sharp superconducting transition with transition width 0.4 K. We also found that the samples possess very large current carrying ability and high upper critical fields, indicating potential applications requiring very high field. The above simple and safe one-step technique of single crystal growth can be effective in other systems of Fe-based superconductors.