Politecnico di Milano [POLIMI]

Salvatore Stagira

Principal Investigator

Aldo Frezzotti

Team Leader


Caterina Vozzi


Monica Bollani


Pasquale Barbato

PhD student

Valer Tosa

Team leader

Nicoletta Tosa


Robert Riedel


(male, CEO of C5, first-time participant to FET under Horizon 2020) graduated in 2010 from Friedrich-Schiller-University Jena in Physics with focus on photonic integrated circuits and femtosecond laser micromachining (Institute of Applied Physics). He received his PhD in 2013 at the University of Hamburg for his work at DESY, developing high-power femtosecond Lasers and EUV/softX-ray sources and metrology tools. While continuing his work at DESY from 2013 – 2015, he founded Class 5 Photonics with colleagues working in Hamburg, Germany and Stanford, USA. Together with his team, he received several innovation awards.

Jan Heye Buss


(male, CTO at C5, first-time participant to FET under Horizon 2020)
Graduated in 2008 from Ruhr University of Bochum in Physics (BA Biology/Mathematics 2006) in the field of ultrafast condensed matter spectroscopy of semiconductors. After receiving his PhD in Physics in 2011 studying the ultrafast dynamics of electron spin’s in wide-gap semiconductors he continued his work until 2014 as a post-doctoral fellow in Bochum. From 2014, Heye joined the Material Sciences Division at the Lawrence Berkeley National Laboratory awarded with DFG fellow scholar ship to work 2D materials exploiting a self-designed, high-repetition rate table EUV/soft-Xsource measuring the temporal charge carrier dynamics directly in momentum space. Heye continued his endeavor in EUV/soft-X-source development joining the Class 5 Photonics GmbH EUV team in August 2018.

Philipp Merkl

Project Leader MIR laser sources

(male, Project Leader MIR laser sources at C5, first-time participant to FET under Horizon 2020)
Graduated in 2017 from University of Regensburg in Nanoscience. He received his PhD in Physics in 2021 studying the ultrafast exciton dynamics in atomically thin semiconductors. During his scientific career, he developed and worked with different types of ultrafast laser systems operating in the MIR spectral region, giving access to the dynamics of elementary excitations in solids. He has published >8 peer reviewed articles in high impact journals such as, Nature Publishing Group (Nature Materials and Nature Communications) and Optics Letters. Philipp joined Class 5 Photonics GmbH in Mai 2021 incorporating his experience in MIR laser sources in the development of the XPIC driver laser.