Unusual large magnetostriction in the ferrimagnet Gd(2/3)Ca(1/3)MnO(3)

CORREA V.; N. HABERKORN; G. NIEVA; D. GARCIA; B. ALASCIO

EUROPHYSICS LETTERS

EPL ASSOCIATION

Año: 2012 vol. 98 p. 3703 - 3709

0295-5075

We report an unusual giant linear magnetostrictive effect in the ferrimagnet Gd2/3Ca1/3MnO3 (Tc aprox. 80 K). Remarkably, the magnetostriction, negative at high temperature (T aprox. Tc), becomes positive below 15 K when the magnetization of the Gd sublattice overcomes the magnetization of the Mn sublattice. A rather simple model where the magnetic energy competes against the elastic energy gives a good account of the observed results and confirms that Gd plays a crucial role in this unusual observation. Unlike previous works in manganites where only striction associated with 3d Mn orbitals is considered, our results show that the lanthanide 4f orbitals striction can be also very important and it cannot be disregarded. Remarkably, the magnetostriction, negative at high temperature (T aprox. Tc), becomes positive below 15 K when the magnetization of the Gd sublattice overcomes the magnetization of the Mn sublattice. A rather simple model where the magnetic energy competes against the elastic energy gives a good account of the observed results and confirms that Gd plays a crucial role in this unusual observation. Unlike previous works in manganites where only striction associated with 3d Mn orbitals is considered, our results show that the lanthanide 4f orbitals striction can be also very important and it cannot be disregarded.