1. Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
2. Department of Physics, University of Oxford, OX1 3PU Oxford, United Kingdom
3. XMaS, The U.K.-CRG Beamline, European Synchrotron Radiation Facility, 38043 Grenoble Cedex 09, France
4. Department of Physics, University of Warwick, CV4 7AL Coventry, United Kingdom
5. Center for Nano Optics, Mads Clausen Institute, University of Southern Denmark, 5230 Odense M, Denmark
6. NanoSYD, Mads Clausen Institute, University of Southern Denmark, 6400 Sønderborg, Denmark