Large, controllable spikes of magnetoresistance in La2/3Ca 1/3MnO3/SrTiO3 superlattices

Authors

Sergey A. Fedoseev, University of WollongongFollow
Alexey V. Pan, University of WollongongFollow
Sergey Rubanov, University of Melbourne
Igor A. Golovchanskiy, University of WollongongFollow
Olga V. Shcherbakova, University of WollongongFollow

RIS ID

75150

Publication Details

Fedoseev, S., Pan, A. V., Rubanov, S., Golovchanskiy, I. & Shcherbakova, O. V. (2013). Large, controllable spikes of magnetoresistance in La2/3Ca 1/3MnO3/SrTiO3 superlattices. ACS Nano, 7 (1), 286-293.

Abstract

We have investigated superlattices consisting of up to 30 epitaxial nanomultilayers (3-7 nm thick) of ferromagnetic La2/3Ca 1/3MnO3 (LCMO) and insulating SrTiO3 (STO) hybrids. The superlattices demonstrate dramatic shifts of Curie temperature, indicating the possibility of its tunability. The metal-insulator transition (MIT) has been observed around 140 K. Below the MIT temperature, the superlattices have shown sharp drops of resistivity, facilitating the largest and sharpest magnetoresistance peaks (>2000%) ever observed in LCMO films and superlattices at low temperatures. The observed experimental results can be explained in the frame of the phase separation model in manganites with well-organized structures. The results of magnetic and transport measurements of such hybrid structures are discussed, indicating a magnetodielectric effect in STO interlayers. The magnetic and transport properties of the superlattices are shown to be technology-dependent, experiencing dimensional transitions, which enables the creation of structures with prescribed magnetoresistance characteristics for a broad range of applications.