Electrical transport properties of Nd0.67−x Eu x Sr0.33MnO3 (0 ≤ x ≤ 0.67) manganites
- 105 Downloads
A systematic investigation of electrical transport properties viz., electrical conductivity and thermopower of Eu-doped Neodymium-based colossal magnetoresistive manganites with compositional formula, Nd0.67−x Eu x Sr0.33MnO3 (x = 0–0.67) has been undertaken. These materials were prepared by citrate gel route and characterized by X-ray diffraction, scanning electron microscopy, AC susceptibility, and electrical resistivity measurements. With a view to understand the complex conduction mechanism of these materials, electrical resistivity and thermoelectric power (TEP) data have been analyzed using various theoretical models. It has been concluded that the ferromagnetic metallic part of the conduction mechanism is explained by grain/domain boundary, electron–electron, and magnon scattering mechanisms, while that of high temperature paramagnetic insulating region might be due to small polaron hopping mechanism. The sign change of charge carriers observed in TEP measurements is attributed to the oxygen deficiency of the samples.
KeywordsManganite Electrical Transport Property Compositional Formula Metal Insulator Transition Temperature Adiabatic Small Polaron
One of the authors (G. Venkataiah) is grateful to CSIR, Govt. of India for awarding Research Associate (RA) Fellowship.
- 2.Rao CNR, Raveau B (eds) (1998) Colossal magnetoresistance, charge ordering and other related properties of rare earth manganates. World Scientific, SingaporeGoogle Scholar
- 7.Blatt FJ, Schroeder PA, Foiles CL, Greig D (1976) Thermoelectric power of metals. Plenum, New YorkGoogle Scholar
- 14.Venkataiah G, Venugopal Reddy P (2005) Solid State Commun 136:114Google Scholar
- 15.Young RA (1993) The Rietveld method. Oxford University Press, New YorkGoogle Scholar
- 17.Vogel AI (1978) A text book of quantitative inorganic analysis including elementary instrumental analysis, 4th edn. Longman, LondonGoogle Scholar
- 25.Mott NF, Davis EA (1971) Electronic process in noncrystalline materials. Clarendon, OxfordGoogle Scholar