1. Laboratory of Electron Nanoscopies (LENS-MIND), Department of Electronics and Biomedical Engineering, Universitat de Barcelona, 08028 Barcelona, Spain
2. Institute of Nanoscience and Nanotechnology, Universitat de Barcelona (IN2UB), 08028 Barcelona, Spain
3. Scientific and Technological Centers, Universitat de Barcelona (CCiT-UB), 08028 Barcelona, Spain
4. Instituto de Energía Solar, Universidad Politécnica de Madrid, Avda. Complutense 30, 28040 Madrid, Spain