Single crystal fibre growth of magnetoplumbite family of materials and their properties

Single-crystal fibres of magnetoplumbite structure with compositions MgLaAl11O19 (MLA) and MgNdGaAl10O19 (MNGA) were studied in this work. Since the melting temperatures of MLA and MNGA are high, the laser heated pedestal growth (LHPG) technique was chosen to grow the crystal fibres as it is a powerful method for rapid growth of refractory oxides and does not need to use any crucibles. The crystal growth behaviors were investigated. The as grown crystal fibres were analyzed by X-ray powder diffraction to determine the crystallographic structures and lattice parameters. The X-ray Laue back reflection pattern was presented. Dielectric properties and thermal properties of the materials were examined in terms of their potential applications as substrates of epitaxial growth of high Tc superconducting thin films for microwave devices.