STRONTIUM SUBSTITUTION IN SUPERCONDUCTING RBA(2)CU(4)O(8) (R=GD AND HO) COMPOUND

The effect of substitution of Sr for a part of Ba in superconducting G dBa2Cu4O8 and HoBa2Cu4O8 on critical temperatures and lattice constant s was investigated, The critical temperatures were definitely unchange d in spite of the reduction of the unit cell which was reportedly effe ctive for the enhancement of the critical temperature in the rare-eart h clement substitution, The orthorhombicities of unit cells increased with the Sr content, as resulted from the large shortening of the a ax is compared with the b asis. In the present work, the dependence of th e shortening of each axis on the ionic radius of a rare-earth element was found. (C) 1997 Academic Press.