Aeppli leads the Quantum Technologies Group spanning ETH Zurich, EPFL, and PSI. Research directions: (1) Quantum materials imaging — using SLS synchrotron X-rays (including SwissFEL ultrafast pulses) and neutrons at SINQ to image quantum phase transitions, skyrmions, and correlated phases; non-destructive imaging of device structures; (2) Rare-earth quantum magnets and qubits — LiHoF4 as a model quantum system; Er, Pr, and Nd spin qubits in crystals for quantum information and sensing; (3) Semiconductor quantum devices — silicon and germanium nanostructures probed by synchrotron nanoscale X-ray imaging; (4) Van der Waals materials and CDW memory devices. Strong interface with PSI large-scale facilities as unique quantum sensing tools for materials.