Nanoscale multiphase separation at La2/3Ca1/3MnO3/SrTiO3 interfaces - art.no. 067210

Mn-55 nuclear magnetic resonance experiments are reported on a series of fu lly strained epitaxial La2/3Ca1/3MnO3 thin films on SrTiO3. We have found e vidence of multiple phase segregation into ferromagnetic metallic and nonme tallic regions as well as regions that are nonferromagnetic and insulating. These insulating regions are mainly located close to interfaces and may ha ve a significant impact on the performance of spin-tunnel devices. As a res ult of phase segregation, the ferromagnetic coupling within the metallic re gions is depressed. This accounts for the reduction of the Curie temperatur e and conductivity in nanometric thin films.