Advances on Low-dimensional Perovskite Manganite Nanostructures

In the perovskite-type manganese oxides, multi-degrees of freedom such as charge, spin, orbital and crystal lattice coexist simultaneously, and the strong completing interactions among them result in a series of novel physical phenomena such as colossal magnetoresistance effect, giant magnetic entropy effect, metal-insulator transition, electronic phase separation and charge/orbital ordering, which make them become attractive issues in condensed matter physics. Advances in integration and miniaturization of the electronic devices have resulted in their feature sizes continued to be decreased, and now the feature sizes of electronic devices based on perovskite-type manganese oxides are down-scaled into nanometered sizes. At nanoscale perovskite-type manganese oxides exhibit apparent size effects and possess the electrical and magnetic transport properties that are different from their bulk and film counterparts, which have important applications in the fields of a new generation of microelectronic devices. In recent years, many advances have been made in fabrication, microstructural characterization electrical and magnetic property measurements of the low-dimensional perovskite manganite nanostructures, and also in the theoretical modelling of the resulting properties. In this paper, an overview of the state of art in the low-dimensional perovskite manganite nanostructures is presented. First, the microstructural characterizations of the low-dimensional perovskite manganite nanostructures are reviewed, and then the electronic phase separation and charge ordering phenomena in the low-dimensional perovskite manganite nanostructures are also introduced. Measurements of the electrical and magnetic transport properties at nanoscale are reviewed. Their potential applications in the fields of spintronics, the next-generation magnetic random access memories and gas sensors, are also discussed. Finally, some key problems in the future researches of the low-dimensional perovskite manganite nanostructures are also outlined.