After my PhD in Physics in 2003 on the “Switchable mirror” I obtained a rich international postdoctoral experience with an emphasis on nanoparticles. After working on various topics such as hydrogen storage and magnetism of nanoparticles I started my own research line in 2010 with nanoparticles and light. My current work involves nanoparticles for photovoltaics and light-matter interaction from a more fundamental point of view. I am using (plasmonic) metal and semiconductor (quantum dot) nanoparticles to enhance light trapping in thin film solar cells. Besides this research in novel concept photovoltaics I am studying the plasmonic behaviour of nanoparticles embedded in semiconductors with electron energy loss spectroscopy (EELS) and femto second laser spectroscopy . For this research I use a dedicated gas aggregation magnetron sputter cluster source to fabricate the nanoparticles. This is combined with a thin film magnetron sputter source, with which almost any nanoparticle-thin film composite can be fabricated. Many of the advanced characterisation experiments are performed in international collaborations.