Self-assembling behavior and interface structure in vertically aligned nanocomposite (Pr(0.5)Ba(0.5)MnO(3))(1-x):(CeO(2))(x) films on (001) (La,Sr)(Al,Ta)O(3) substrates

Heteroepitaxial oxide-based nanocomposite films possessing a variety of functional properties have attracted tremendous research interest. Here, self-assembled vertically aligned nanocomposite (Pr(0.5)Ba(0.5)MnO(3))(1-x):(CeO(2))(x) (x = 0.2 and 0.5) films have been successfully grown on single-crystalline (001) (La,Sr)(Al,Ta)O(3) substrates by the pulsed laser deposition technique. Self-assembling behavior of the nanocomposite films and atomic-scale interface structure between Pr(0.5)Ba(0.5)MnO(3) matrix and CeO(2) nanopillars have been investigated by advanced electron microscopy techniques. Two different orientation relationships, (001)[100](Pr0.5Ba0.5MnO3)//(001)[1-10](CeO2) and (001)[100](Pr0.5Ba0.5MnO3)//(110)[1-10](CeO2), form between Pr(0.5)Ba(0.5)MnO(3) and CeO(2) in the (Pr(0.5)Ba(0.5)MnO(3))(0.8):(CeO(2))(0.2) film along the film growth direction, which is essentially different from vertically aligned nanocomposite (Pr(0.5)Ba(0.5)MnO(3))(0.5):(CeO(2))(0.5) films having only (001)[100](Pr0.5Ba0.5MnO3)//(001)[1-10](CeO2) orientation relationship. Both coherent and semi-coherent Pr(0.5)Ba(0.5)MnO(3)/CeO(2) interface appear in the films. In contrast to semi-coherent interface with regular distribution of interfacial dislocations, interface reconstruction occurs at the coherent Pr(0.5)Ba(0.5)MnO(3)/CeO(2) interface. Our findings indicate that epitaxial strain imposed by the concentration of CeO(2) in the nanocomposite films affects the self-assembling behavior of the vertically aligned nanocomposite (Pr(0.5)Ba(0.5)MnO(3))(1-x):(CeO(2))(x) films.