1. Department of Physics, CICECO – Aveiro Institute of Materials University of Aveiro Aveiro 3810‐193 Portugal
2. Instituto de Telecomunicações and University of Aveiro Campus Universitário de Santiago Aveiro 3810‐193 Portugal
3. Department of Chemistry, CICECO – Aveiro Institute of Materials University of Aveiro Aveiro 3810‐193 Portugal
4. Department of Biology, CESAM University of Aveiro Aveiro 3810‐193 Portugal
5. Department of Electrical and Computer Engineering, Instituto de Telecomunicações Instituto Superior Técnico Universidade de Lisboa Lisbon 1049‐001 Portugal