1. Institut d'Electronique Fondamentale, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay, France
2. Institut Néel, CNRS and Université Grenoble Alpes, BP 166, F-38042 Grenoble Cedex 9, France
3. Central Research Institute of Electric Power Industry, Yokosuka, Kanagawa 240-0196, Japan
4. Singulus Technology AG, Hanauer Landstrasse 103, 63796 Kahl am Main, Germany