Ternary Ba-Fe-As system has been studied to determine a primary solidification field of the BaFe$_2$As$_2$ phase. We found that the BaFe$_2$As$_2$ phase most likely melts congruently and primarily solidifies either in the FeAs excess or Ba$_{ x}$As$_{ 100-x}$ excess liquid. Knowing the primary solidification field, we have performed the vertical Bridgman growth using the starting liquid composition of Ba$_{ 15}$Fe$_{ 42.5}$As$_{ 42.5}$. Large single crystals of the typical size 10x4x2 mm$^3$ were obtained and their quality was confirmed by X-ray Laue and neutron diffraction.
Categories: cond-mat.supr-con cond-mat.mtrl-sci