Preparation, microstructural and electrical characterization of SrVO3 single crystal fiber

Two different processing routes have been adapted for the single-crystal fiber growth of strontium vanadate (SrVO3) by the laser-heated pedestal growth (LHPG) method. These processes use only one step for calcination, sintering, melting, reduction and solidification of the raw material. Single-crystal fibers have been grown from mixtures of SrCO3, VO2 and V2O5 powders in the cylindrically compacted powders geometry, appropriate molar ratio and controlled atmosphere. The products, 15-20 mm in length and 0.6 mm in diameter, black metallic in color with layered structure, are single phase and among the largest in size up to our knowledge. They have been studied with respect to their compositions, microstructural and electrical properties by microprobe analysis, X-ray Laue diffraction and a.c. resistivity measurements, respectively. A slightly different cationic concentration was found for both cases although similar single-crystal quality is separately evidenced. Electrical resistivity measurements along the fibers axis in the temperature range 10-270 K indicate remarkable enhanced conductivity when compared to those reported on polycrystals and smaller single crystals obtained by other ceramic processing routes and crystal growth techniques. (C) 2000 Published by Elsevier Science B.V. All rights reserved.