Electronic phase separation in epitaxial La2/3Ca1/3MnO3 films on (001) and (110) SrTiO3 substrates

We report here on the structural and magnetic characterization of La2/3Ca1/3MnO3 epitaxial films on (001) and (110) SrTiO3 substrates. The (001) films display depressed magnetic properties (lower Curie temperature and magnetization) with respect to the bulk counterpart values. In contrast, the (110) films invariably display optimal magnetic properties. Mn-55 nuclear magnetic resonance experiments show that, in contrast to (001) films, the (110) films do not show traces of electronic phase separation and thus provide evidence that no weakening of double exchange coupling at interfaces takes place in (110) films. (C) 2006 American Institute of Physics.