1. Physics of Functional Materials, University of Vienna, 1090 Vienna, Austria
2. Christian Doppler Laboratory for Advanced Magnetic Sensing and Materials, 1090 Vienna, Austria
3. Institute of Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
4. Magnetfabrik Bonn GmbH, 53119 Bonn, Germany