1. Department of Physics, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium
2. Mines Saint-Étienne, Université Lyon, INSERM, U 1059 Sainbiose, Centre CIS, F, Saint-Étienne 42023, France
3. Department of Electromechanical Engineering, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium