1. Phantom‐g CICECO–Aveiro Institute of Materials Physics Department University of Aveiro Aveiro 3810‐193 Portugal
2. ICGM CNRS, ENSCM Univ. Montpellier Montpellier 34095 France
3. Institut Universitaire de France (IUF) 1 rue Descartes Paris Cedex 05, 75231 France