Poly and single-domain crystals of TmBa2Cu3O7-d

Works on the synthesis and study of the high-temperature superconductors of various structural types has begun in our Laboratory shortly after their discovery. The first results has been published at the International Conference on HTSC, Interlaken, 1988.

Since all these materials have incongruent character of melting, the flux growth has to be used. This method allowed to grow cm-sizes high-quality single crystals of the La2-xMxCuO4 (M = Ca, Sr, Ba), Ln2-xCexCuO4 (Ln = Pr, Nd, Sm, Eu, Gd), RBa2Cu3O7-d (R = Y, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb), Bi2Sr2- xCaxCuO6+y, Bi2Sr3-xCaxCu2O8+y.

The main attention was paid to RBa2Cu3O7-d crystals. Influence of the kind of rare-earth elements, isomorphous substitutions, crystal growth conditions such as the melts composition, cooling rate, surrounding atmosphere, was studied. The best superconducting properties with the TC = 89-93 K and the transition width of about 0.2 K were found for the crystals with Tm and Y. Some of these crystals were free from twins and suitable for precision investigations of the atomic structure and physical properties. Furthermore, a new effective method of detwinning was worked out which consists of thermomechanical treatment of crystals under reduced oxygen partial pressure. It was found that the crystals with a few large domain can show sharp anomalies of conductivity at the superconducting transitions which may be attributed to a small difference of TC value (~ 1K) in the vicinity of the twin boundaries and in the bulk of crystals. The single domain crystals were used for the studies of their atomic structure, lattice dynamics, vortex pinning and other properties.


Main publications:

  1. Crystal growth and properties of the RBa2Cu3O7-y - family crystals. V.I.Voronkova, I.V.Vodolazskaya, V.K.Yanovskii. Superconductivity: Physics, Chemistry, Technique, 1989, v.2, p.50.

  2. Behavior of the superconducting compounds RBa2Cu3O7-y at high temperatures. V.K.Yanovskii, V.I.Voronkova, I.V.Vodolazskaya, I.N.Leont'eva, T.P.Petrovskaya. Superconductivity: Physics, Chemistry, Technique, 1989, v.2, p.40.

  3. Single crystals of La2-xSrxCuO4-y. V.I.Voronkova and V.K.Yanovskii. Superconductivity: Physics, Chemistry, Technique, 1989, v.2, p.81.

  4. Single-domain crystals of YBa2Cu3O7-d and TmBa2Cu3O7-d. V.I.Voronkova, I.V.Vodolazskaya, and V.K.Yanovskii. Physica C, 1989, v.162-164, p.1211.

  5. Growth and superconductivity of the Bi2Sr2-xCaxCuO6+d and Bi2Sr3-xCaxCu2O8+d single crystals. V.I.Voronkova, A.A.Gippius, V.V.Moshchalkov, V.K.Yanovskii. Superconductivity: Physics, Chemistry, Technique, 1990, v.3, p.1135.

  6. Synthesis of single domain superconductor TmBa2Cu3O7-d and its atomic structure. V.I.Voronkova, V.K.Yanovskii, V.N.Molchanov, N.I.Sorokina, V.I.Simonov. JETP Letters, 1990, v.52, p.224.

  7. Bi-based superconductors and their surface wave velocities. V.V.Aleksandrov, T.S.Velichkina, V.I.Voronkova, A.A.Gippius, S.V.Red'ko, I.A.Yakovlev, and V.K.Yanovskii. Solid State Commun., 1990, v.76, p.685.

  8. The full Meissner effect in the untwinned TmBa2Cu3Ox single crystal. V.V.Moshchalkov, A.A.Zhukov, V.D.Kuznetsov, V.V.Metlushko, V.I.Voronkova, V.K.Yanovskii. Solid State Commun., 1990, v.74, p.1295.

  9. Hypersound studies of the electron doped Ln2-xCexCuO4 and hole doped La2-xMxCuO4 high-TC single crystals. V.V.Aleksandrov, T.S.Velichkina, I.V.Vodolazskaya, V.I.Voronkova, I.A.Yakovlev, and V.K.Yanovskii. Solid State Commun., 1992, v.82, p.669.

  10. Thermomechanical detwinning of superconducting YBa2Cu3O7-x single crystals under reduced oxygen partial pressure. V.I.Voronkova, V.K.Yanovskii, and Th.Wolf. Superconductivity: Physics, Chemistry, Technique, 1993, v.6, p.1529.

  11. Growth, morphology and superconducting properties of TmBa2Cu3O7-d single crystals. V.I.Voronkova, V.K.Yanovskii, Th.Wolf, E.W.Seibt, A.A.Zhukov, S.A.Klestov, V.N.Molchanov, N.I.Sorokina, V.I.Simonov. J.Crystal Growth, 1995, v.149, p.74.

  12. Growth, detwinning and properties of YBa2Cu3Ox and TmBa2Cu3Ox single crystals. V.I.Voronkova, V.K.Yanovskii. Growth of Crystals. V.20. Consultants Bureau, N.Y.,1996, pp.153-169.

  13. Ferroelastic domains in RBa2Cu3O7-d crystals. V.I.Voronkova and V.K.Yanovskii. Ferroelectrics, 1997, v.191, p.275.

  14. Single domain superconductor TmBa2Cu3O7-d: Crystal growth and atomic structure. N.I.Sorokina, V.N.Molchanov, V.I.Voronkova, V.K.Yanovskii, V.I.Simonov. Crystallography Reports, 1999, v.42, p.567.



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