Enhanced nonlinear current–voltage behavior in Au nanoparticle dispersed CaCu3Ti4O12 composite films

An enhanced nonlinear current–voltage behavior has been observed in Au nanoparticle dispersed CaCu3Ti4O12 composite films. The double Schottky barrier model is used to explain the enhanced nonlinearity in I–VI–V curves. According to the energy-band model and fitting result, the nonlinearity in Au: CCTO film is mainly governed by thermionic emission in the reverse-biased Schottky barrier. This result not only supports the mechanism of double Schottky barrier in CCTO, but also indicates that the nonlinearity of current–voltage behavior could be improved in nanometal composite films, which has great significance for the resistance switching devices.

► Au nanoparticle dispersed CaCu3Ti4O12 films were prepared by PLD.
► An enhanced I–VI–V behavior is observed in such composite films.
► This result supports the mechanism of double Schottky barrier in CaCu3Ti4O12.
► It is a new method to increase the I–VI–V nonlinearity of perovskite oxide film.