Published online by Cambridge University Press: 28 February 2011
(Y,Ho)‐Ba‐Cu‐0 superconductors with the high critical current densities (Jc) in an applied magnetic field have been synthesized by a unidirectional melt solidification method. Melt solidified bulk materials are composed of large plate‐shape (Y,Ho)Ba2Cu3Oy crystals which contain small (∼5 um) particles of (Y.Ho)2BaCuO5. The Jc value of the melt solidified (Y,Ho)‐Ba‐Cu‐0 sample is ∼10000 A/cm2 at 77K, H = IT and this value is much higher than the value of 4200 A/cm2 of the melt solidified Y‐Ba‐Cu‐O sample.