Microstructural characteristics of La0.7Ca0.3MnO3 films and multilayers

La0.7Ca0.3MnO3 (LCMO) films and La0.7Ca0.3MnO3/Gd0.7Ca0.3MnO3 (LCMO/GCMO) m ultilayers have been prepared by pulsed laser deposition. The microstructur es of both systems were investigated by transmission electron microscopy (T EM). The main structure of the films and the multilayers was monoclinic wit h a unit cell of size 2a(p) x root 2a(p) x root 2a(p), where a(p) is the la ttice constant of single perovskite crystal. The LCMO films were composed o f three-dimension multitwinning domains, while the LCMO/GCMO multilayers sh owed two-domain structure. In LCMO/GCMO multilayers, LCMO layers were coher ent with GCMO layers and the interfaces between LCMO and GCMO layers were f ree from mismatch dislocation, which resulted in highly strained multilayer d structures.