GROWTH OF SUPERCONDUCTING PB0.5SR2.5Y0.5CA0.5CU2OY SINGLE-CRYSTALS FROM CHARGES CONTAINING SILVER

Single crystals of Pb(0.5)Sq(2.5)Y(0.5)Ca(0.5)Cu(2)O(y) have been grow n by a self-flux technique with excess of CuO and adding 10% (by wt) o f AgNO3 to the starting charge. The grown crystals exhibited tetragona l structure having lattice parameters a = 3.813 Angstrom and c = 11.78 5 Angstrom. The crystals are found to undergo a metal to superconducto r transition at 50 K. Crystals grown without any silver addition did n ot shown any transition to the superconducting down to 15 K. These res ults show that the addition of silver facilitates the oxygenation of c rystals.