About us
The activities of the Max Planck Fellow Group started in 2007. We do basic research in the field of solid state theory. We are interested in a material-specific and parameterfree description of nanostructured systems. Our research is based on the density functional theory formulated in terms of Green functions. Green functions are very comfortable for the consideration of systems with arbitrary geometry like heterostructures, thin films, surfaces, adatoms on surfaces or nanocontacts. The numerical effort of our method scales with the number of atoms. In this respect we are able to treat nanostructures of realistic size.
Our investigations start from the atomic structure of a system which is either known from experiment or can be determined numerically by structural relaxation. The main focus of our work is the microscopic understanding of the electronic, the magnetic, the ferroelectric and the transport properties on the atomic scale.
A substantial part of our research is dedicated to the emerging field of spintronics. Spintronics has a large potential for future applications in sensor and information technology in which the charge and the spin-degree of freedom of the electrons are exploited. A successful application requires achieving control of the materials and processes involved on the atomic scale. To support the experimental developments, to predict new materials and to optimize the effects, first-principle electronic structure calculations based on density functional theory are the most powerful tool. Our method is applied to gain insight into the microscopic origin of spin-dependent transport of magnetic heterostructures as well as metallic and molecular contacts. The basic effects of spintronics like Giant Magnetoresistance (GMR), Tunneling Magnetoresistance (TMR) and Ballistic Magnetoresistance (BMR) have been investigated.
Our research is as well related to the Collaborative Research Centre 762: Functional oxide interfaces. In this respect our activities are extended from metal to metal-oxide heterostructures. We are particularly interested in multiferroics. Multiferroic materials show ferroelectric and magnetic order simultaneously. The observed electric polarization and magnetization and their coupling effects are usually very small in single phase multiferroics. A breakthrough in this respect is expected from multiferroic heterostructures. Magnetoelectric coupling via the interface between a ferroelectric and a ferromagnetic layer is expected to be larger because of the reduced dimensionality.
