Growth rate dependence of the NdFeO3 single crystal grown by float-zone technique

Rare-earth orthoferrite single crystal NdFeO3 has been successfully grown by the floating-zone technique using a four-mirror-image furnace with flowing air. The polycrystalline feed and seed rods were prepared at a pressure of 150 MPa and sintered at 1200 degrees C. Structural characteristics of NdFeO3 single crystal were studied using a metallurgical microscope and by scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX). X-ray diffraction pattern of the crystal with perfect shape indicated the excellent quality of the crystal grown at 9 mm/h without any shoulder, clarifying the absence of subgrain. Particular attention was given to the influence of growth rate on structural properties of the crystals. The X-ray rocking curve of the crystal has a small full-width at half-maximum (FWHM), confirming the high crystal quality of the sample. The results indicate that the optimal growth condition was 9 mm/h growth rate and 5 L/min air flow, compared with the use of other growth rates (3 and 6 mm/h). The growth rate plays an important role in NdFeO3 single crystal growth by the floating-zone technique. (C) 2010 Elsevier B.V. All rights reserved.