1. Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne-EPFL, 1015 Lausanne, Switzerland and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand
2. National Institute of Materials Physics, Atomistilor Street 105 bis, Magurele, Ilfov 77125, Romania
3. Gesellschaft für Schwerionenforschung (GSI), Planckstraße 1, D-64291 Darmstadt, Germany