Magnetic and magnetotransport properties of misfit cobaltate Ca.sub.3./sub.Co.sub..3.93./sub.O.sub.9+δ./sub..

0379113 - FZÚ 2013 RIV US eng J - Článek v odborném periodiku
Hejtmánek, Jiří - Knížek, Karel - Maryško, Miroslav - Jirák, Zdeněk - Sedmidubský, D. - Jankovský, O. - Huber, Š. - Masschelein, P. - Lenoir, B.
Magnetic and magnetotransport properties of misfit cobaltate Ca₃Co_.3.93O_9+δ.
Journal of Applied Physics. Roč. 111, č. 7 (2012), "07D715-1"-"07D715-3". ISSN 0021-8979. E-ISSN 1089-7550
Grant CEP: GA ČR GA203/09/1036
Výzkumný záměr: CEZ:AV0Z10100521
Klíčová slova: low temperature thermoelectric power * magnetic properties
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 2.210, rok: 2012

Samples of Ca3Co3.93O9+δ, prepared by classical ceramic route (CCR) and spark plasma sintering (SPS), were characterized by means of magnetic, electrical, and thermal experiments in a broad temperature range. The low temperature specific heat measured down to 0.3 K, reveals two important electronic contributions: the first one, dominated by magnetic excitations, that can be suppressed by an external magnetic field, and the second, due to band-like carriers, characterized by γ~50 mJ mol-1 K-1 for both samples. The ferrimagnetism, associated with the long-range magnetic order of IS Co3+ species in rock-salt blocks detected below TF~15 K in the CCR samples, is absent in the SPS samples.
Trvalý link: http://hdl.handle.net/11104/0210379