Structural, electrical, magnetic, elastic, and internal friction studies of Nd _(1-x)Ca _xMnO _3 (x=0.2, 0.33, 0.4, and 0.5) manganites

摘要

A series of Nd _(1-x)Ca _xMnO _3 (x=0.2, 0.33, 0.4, and 0.5) manganites was prepared by sol-gel route by sintering at 1300 °C, mainly to understand the correlation between electron, spin, and phonon couplings. The internal friction and longitudinal modulus along with electrical and magnetic properties have been measured. All the samples are found to exhibit anomalies at T _C, T _N, and T _(CO) transition temperatures. The anomalies in longitudinal modulus and the internal friction peak at T _(CO) are attributed to JahnTeller effect. A strong correlation between the temperature dependent elastic, anelastic, resistivity, and ac susceptibility properties has been observed and an effort has been made to explain the observed anomalous behavior by a qualitative model.