Landragin directs SYRTE and its Cold Atom Interferometry and Inertial Sensors team, which develops light-pulse atom interferometers as absolute gravimeters and gyroscopes: the Cold Atom Gravimeter (CAG), whose single-laser pyramid-reflector design he co-invented and commercialized through the start-up Muquans (now Absolute Quantum Gravimeter, AQG), and continuously-operating cold-atom gyroscopes reaching record joint sensitivity. Applications span geodesy, hydrology, volcano monitoring and inertial navigation. He received the CNRS Innovation Medal in 2020.