Band structure determination of well-defined multiferroic heterostructures

• Applicant: Dr. Anke Sander
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2014 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 252867643

In the past few years, novel electronics have been explored which utilize the multifunctional properties of transition metal oxides. Thereby, heterostructures consisting of different materials are of particular interest since they offer on the one hand a combination of the different intrinsic properties and on the other hand also allow for new effects arising at the interface. In these multiferroic heterostructures the properties of the magnetic material depend on the polarization direction of the adjacent ferroelectric layer caused by modifications in the spin-dependent electronic structure. To derive an explanation for the origin of this magnetoelectric coupling at the interface, the central aim of this project is the band structure determination of the magnetic material in dependence of the ferroelectric polarization direction. Therefore, ultra-thin ferroelectric films (BiFeO3, BaTiO3) will be epitaxially grown on thin magnetic La1-xSrxMnO3 films by pulsed laser deposition. By specific control of the termination of the La1-xSrxMnO3 film a defined and homogenous orientation of the spontaneous polarization can be achieved. Such grown heterostructures will afterwards be characterized by photoelectron spectroscopy without breaking the ultra-high vacuum conditions. Especially, spin-resolved measurements of the band structure of the magnetic component allow for the determination of the charge carrier density in each spin channel.

• DFG Programme: Research Fellowships
• International Connection: France
• Host: Dr. Manuel Bibes