Double Exchange in Electron Doped Ca1-xYxMnO3 Manganites

Дата и время публикации : 2000-10-19T18:57:58Z

Авторы публикации и институты :
H. Aliaga
M. T. Causa
A. Butera
B. Alascio
H. Salva
M. Tovar D. Vega
G. Polla
G. Leyva
P. Konig

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 8 pages, 10 figures, updated 07/05/00
Первичная категория: cond-mat

Все категории : cond-mat

Краткий обзор статьи: 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<x<0.25. We found that in the paramagnetic regime, the magnetic susceptibility, chi, deviates substantially from a Curie-Weiss law for x>0. With a simple model where antiferromagnetic (AF) superexchange and ferromagnetic (FM) double exchange (DE) compete, we fit the experimental chi(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.

Category: Physics