PhD vacancy at the Centre for Quantum Information and Communication (QuIC) at the Université Libre de Bruxelles (ULB) in Belgium. The general research topic will be the theoretical study of photonic quantum circuits and their applications to quantum technologies. The research will be done under the supervision of Prof. Nicolas Cerf (ULB) in close collaboration with Dr. Leonardo Novo (INL, International Iberian Institute of Nanotechnology, Portugal).