Crystal growth and thermoelectric properties of CaMn0.98Nb0.02O3-delta

Thermoelectric CaMn0.98Nb0.02O3-delta single crystals were grown from sintered polycrystalline material using the traveling-solvent floating zone (TSFZ) method. The floating-zone furnace was operated at over-pressure using an Ar/O-2 mixture to prevent evaporation during the growth process. Six twin-domain variants were detected with single-crystal X-ray diffraction (XRD) and confirmed by electron diffraction (ED) and high-resolution transmission electron microscopy (HRTEM). The Seebeck coefficient (S) of the single-crystalline material indicates n-type semiconducting behavior. Within 10 K < T < 125 K a negative peak in S is observed, known to be characteristic of antiferromagnetic ordering. The ferromagnetic long-range ordering, expected on the basis of double exchange between Mn4+ and doped Mn3+ species, thus appears to remain suppressed in the single-crystalline material. © 2013, Elsevier Ltd.

Keywords

Crystal growth, Crystals, Magnetic properties, Perovskite, Calcium, Conversion

Citation

Alfaruq, D. S., Aguirre, M. H., Otal, E. H., Populoh, S., Karvonen, L., Yoon, S., Lu, Y., Deng, G., Ebbinghaus, S. G., & Weidenkaff, A. (2013). Crystal growth and thermoelectric properties of CaMn0.98Nb0.02O3-delta. Journal of Crystal Growth, 377, 170-177. doi:10.1016/j.jcrysgro.2013.05.020