Rectifying characteristic of perovskite oxide La1.89Ce0.11CuO4/Ba0.5Sr0.5TiO3/La0.67Sr0.33MnO3 heterostructures

Heterostructure composed of electron-doped high-T-c superconductor La1.89Ce0.11CuO4 (LCCO), ferroelectric Ba0.5Sr0.5TiO3 (BST) and colossal magnetoresistance (CMR) La0.67Sr0.33MnO3 (LSMO) thin films were deposited on the (001) SrTiO3 (STO) substrate by pulsed laser deposition method. The current-voltage measurement shows that the LCCO/BST/LSMO structure has strong rectification comparing to the LCCO/LSMO, LCCO/BST and BST/LSMO bilayer structures. The experiment indicates that both the BST and LCCO layers play important roles in the rectifying effect in the oxide heterostructures. We discuss the mechanism of their rectification based on the energy band bending as well as the depletion and the diffusion of the charge carriers at the interfaces. The growth conditions and the multilayer features as well as the properties of individual material in the heterostructures were also investigated. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3662909]