.

Complex cobalt oxide perovskites with general formula RBaCo₂O_5+x (R=rare earth) have been attracted considerable interests because of their interesting properties: magnetic and metal-insulator transitions, giant magnetoresistance, ionic conductivity and a structural similarity to high temperature superconductors. All the compounds are oxygen non-stoichiometric (0 <x<1) and the cobalt cations can adopt different oxidation and spin states. Growing of single crystals of these materials is very difficult. Preliminary studies of pseudobinary phase diagrams RCoO₃-BaCoO₃ (R=Pr, Ho and Tb) have been shown that the compounds melt incongruently and the primary crystallization fields are very narrow. Crystal growth experiments have been performed using Traveling Solvent Floating Zone method using a mirror furnace. Generally, during the crystal growth experiments it has been difficult to stabilize the floating zone, especially for very low growing rates (below 0.5 mm/h). The resulting materials were often polycrystalline with many cracks. From many experiments performed, the best results have been obtained in the case of R=Tb and Nd. For these two systems good quality single crystals in size of several mm³ could be obtained. For these crystals measurements of magnetization, resistivity, specific heat, thermopower, neutron diffraction and muon spin rotation have been performed.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/9750 must be provided.

1. Cuprate spin ladder crystals grown by floating zone method under elevated oxygen pressure
2. Layered cobaltites: synthesis, oxygen nonstoichiometry, transport and magnetic properties
3. Anharmonicity and weak modes assignment in LaSrCuO with oxygen isotopic substitution
4. Giant magnetoresistivity in single crystals of rare earth layered cobaltites