Crystal Growth and Superconductivity of Tl-Ca-Ba-Cu-O System

Abstract

Single crystals of oxides in the Tl-Ca-Ba-Cu-O system with the general formula Tl 2 Ca n -1 Ba 2 Cu n O x ( n =1, 2, 3, 4) have been successfully grown by the flux method. All crystals were of the platelet form ranging from 0.6 to 5 mm 2 . The transition temperatures of as-grown crystals, determined by DC SQUID magnetometer, were 84 K, 110 K, and 118 K for n =1, 2, and 3, respectively, but slightly lower for 115 K, where n =4. The results of the differential thermal analysis (DTA), X-ray diffraction measurement and energy dispersive X-ray microanalysis (EDX) will be also reported.