1. IHP GmbH, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany
2. Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education and International Center for Dielectric Research, Xi'an Jiaotong University, 710049 Xi'an, China
3. Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, Via Roberto Cozzi 55, 20125 Milano, Italy
4. Laboratory for Solid State of Physics, ETH Zürich, Otto-Stern-Weg 1, 8093 Zürich, Switzerland
5. Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, 00146 Rome, Italy
6. BTU Cottbus Senftenberg, Institute of Physics and Chemistry, Konrad Zuse Str.1, 03046 Cottbus, Germany