Department of Physics, Tampere University of Technology, Tampere, Finland. artturi.koivuniemi@vtt.fi|Department of Physics, Tampere University of Technology, Tampere, Finland. artturi.koivuniemi@vtt.fi|Department of Physics, Tampere University of Technology, Tampere, Finland. artturi.koivuniemi@vtt.fi|Department of Physics, Tampere University of Technology, Tampere, Finland. artturi.koivuniemi@vtt.fi|Department of Physics, Tampere University of Technology, Tampere, Finland. artturi.koivuniemi@vtt.fi