Magnetotransport and Hall effect studies of SrRuO_3/SrTiO_3 superlattices

摘要

Good epitaxial growth characteristics make oxide heterostructures of the perovskite family a model system for the study of emerging phenomena at interfaces. Here we report on SrRuO_3/SrTiO_3 superlattices as well as single films with individual layer thicknesses between two and 20 unit cells fabricated by pulsed laser deposition. Coherent growth of the interfaces was confirmed by X-Ray and high resolution transmission electron microscopy measurements. Special attention is dedicated to the study of the ordinary and anomalous Hall effect. While SrRuO_3 single layers as thin as three unit cells and superlattices with individual layer thicknesses above four unit cells show an anomalous Hall effect similar to the bulk and a temperature-independent high field Hall slope, the ultrathin superlattice shows a temperature dependence in the high field Hall slope and opposite sign in the anomalous Hall effect. Additionally, angle dependent magnetotransport was used to obtain structural information.