Large single crystal growth of BaFe1.87Co0.13As2 using a nucleation pole

TL;DR

This paper reports a method for growing high-quality BaFe1.87Co0.13As2 single crystals using a nucleation pole, demonstrating their superconducting properties with sharp transition temperatures and strong magnetic shielding.

Contribution

The study introduces a novel crystal growth technique employing a nucleation pole, enabling the production of large, high-quality superconducting crystals.

Findings

Crystals up to 20 x 10 x 2 mm3 were successfully grown.

Superconducting transition temperature Tc~25 K was observed.

Magnetic susceptibility confirmed nearly 100% shielding fraction.

Abstract

Co-doped iron arsenic single crystal of BaFe1.87Co0.13As2 with dimension up to 20 x 10 x 2 mm3 were grown by a nucleation pole: an alumina stick served as nucleation center during growth. The high quality of crystalline was illustrated by the measurements of neutron rocking curve and X-ray diffraction pattern. A very sharp superconducting transition temperature Tc~25 K was revealed by both resistivity and susceptibility measurements. A nearly 100% shielding fraction and bulk nature of the superconductivity for the single crystal were confirmed using magnetic susceptibility data.