Single crystal growth of Tl-based superconductors

✍ Scribed by H.M. Duan; T.S. Kaplan; B. Dlugosch; A.M. Hermann; J. Swope; J. Drexler; P. Boni; J. Smyth

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 645 KB
• Volume: 203
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(92)90031-7

✦ Synopsis

Large single crystals of TlrBazCuOs and TlzBarCaCuzOs superconductors were grown by a two-step self-flux process. In the first step, a mixture of T1203, BaO (and CaO for 2212 crystals) and CuO was heated at 940°C for about ten minutes to form bulk superconductors. In the second step, the bulk compound was reground, re-pelletized and placed into an AlrOx crucible which was then sealed. The sealed crucible was heated up to above melting point of the bulk superconductor. The crystals were grown as the temperature cooled down slowly. Crystals are plate-like with in-plane crystal size as large as 12 mm X 8 mm and the thickness range from 20 pm to 0.8 mm. X-ray diffraction experiments, SEM and other chemical analysis results have shown the crystals to be of high quality and chemically uniform.