1. Consiglio Nazionale delle RicercheIstituto per la Microelettronica e Microsistemi Via del fosso del cavaliere 100 00133 Rome Italy
2. Group of Displays and Photonic Applications (GDAF)Department of Electronic TechnologyCarlos III University of Madrid Madrid 28911 Spain
3. Sensors and Instrumentation Techniques (SIT)Department of Electronic TechnologyCarlos III University of Madrid Madrid 28911 Spain
4. Physics InstituteGoethe University Frankfurt am Main 60438 Frankfurt am Main Germany