Crystal Growth Laboratory

The growth of high quality single crystals is an essential technology for fundamental research in solid state physics. As a simple statement it could be brought to the point that the measurements of physical properties on new materials are always only as good as the samples are. To study the intrinsic physical properties of a new material in most cases only the use of single crystals of high quality leads to unambiguous results. Also many properties of anisotropic materials can only be measured when single crystals are available.

The Walther-Meißner-Institute operates a crystal growth laboratory since 2000. It is equipped with state of the art techniques for the growth of high purity crystals of transition metal oxides. This includes the equipment for the fabrication of the polycrystalline starting materials (various furnaces, simultanious thermal analysis combining thermogravimetry (TG) with differential thermal analysis (DTA) or dynamic differential calorimetry (DSC), ball mills, granulometric analysis, etc.) as well as a 4- mirror image furnace for the growth of oxide single crystals using the traveling solvent floating zone method.

The research focus of Walther-Meißner-Institute is mainly on oxide materials. Therefore the crystal growth laboratory is specialized on the growth and characterization of oxide single crystals and polycrystalline bulk materials. Among the compounds studied at present are:

1. Nearly all the families of the high temperature superconductors such as:
   • REBa₂Cu₃O_7-δ (RE = rare earths)
   • Bi-2223, Bi-2212 und Bi-2201
   • La_2-xSr_xCuO₄, Pr_2-xCe_xCuO₄ and Nd_2-xCe_xCuO₄
2. Magnetically ordering compounds such as:
• Ferromagnetic double perovskites, Magnetite or ZnO
3. Bulk detector crystals such as:
   • CaWO₄