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Single-crystal growth of the ternary BaFe$_2$As$_2$ phase using the vertical Bridgman technique

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 نشر من قبل Taku J. Sato
 تاريخ النشر 2008
  مجال البحث فيزياء
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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.



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