1. VTT Technical Research Center of Finland, Espoo, Finland, Department of Applied Physics, Aalto University School of Science and Engineering, Finland, Department of Physics, Tampere University of Technology, Finland, INSERM URM-S665, DSIMB, Paris, France, Department of Biochemistry & Biophysics, Stockholm University, Stockholm, Sweden, and MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Denmark