Physics Department, University of Gothenburg, 412 96, Gothenburg, Sweden. johan.akerman@physics.gu.se.
Department of Applied Physics, School of Engineering Sciences, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden. johan.akerman@physics.gu.se.
Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan. johan.akerman@physics.gu.se.
Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan. johan.akerman@physics.gu.se.