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Double Exchange in Electron Doped Ca1-xYxMnO3 Manganites

H. Aliaga·M. T. Causa·A. Butera·B. Alascio·H. Salva·M. Tovar D. Vega·G. Polla·G. Leyva·P. Konig
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Abstract

We have studied structural, magnetic and transport properties as a function of temperature and magnetic field in the electron doped manganite YxCa1-xMnO3, for 0 0. With a simple model where antiferromagnetic (AF) superexchange and ferromagnetic (FM) double exchange (DE) compete, we fit the experimental χ(x, T) obtaining parameter values which indicate that the FM-DE interaction is about twice as intense as the AF interaction. In the ordered phase, the H-dependence of the magnetization M(x,T) is explained in terms of magnetic polarons. We propose that the displacement of the eg electrons (in the G-type AF background) causes the alignement of the polaron with H. Signatures of polaronic behavior were also found in the x and T dependence of the electric resistivity.

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H. Aliaga, M. T. Causa, A. Butera, B. Alascio, H. Salva, M. Tovar D. Vega, G. Polla, G. Leyva, P. Konig. 2001-09-13. Double Exchange in Electron Doped Ca1-xYxMnO3 Manganites. https://arxiv.org/abs/cond-mat/0010295

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