Crystal growth of high T_c cuprate superconductors

In the first part, the critical factors in the growth of YBa2Cu3O7-x (123) crystals are addressed. We emphasize the advantages of nucleation on gold surfaces and the subsequent flow of the flux away from the crystals to leave well formed isolated free crystals. The second part describes the crystal growth of layered bismuth cuprates, stressing the influence of composition on the occurrence of superconductivity in Bi2Sr2-xCuOx. Finally, we describe a simple ac susceptibility measurement to be used as a standard for comparison of Tc for crystals grown under different conditions. © 1988.