1. Institute of Geophysics, ETH Zurich, 8092 Zurich, Switzerland
2. Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
3. Laboratory of Inorganic Chemistry, ETH Zurich, 8093 Zurich, Switzerland
4. Institute of Functional Interfaces, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany