On May 15-17, the PIER-funded workshop on cavity-based control of materials took place at the Center for Free Electron Laser Science. With around 80 participants, the workshop brought world-leading experts in the field together with a large number of mostly early career scientists.

Electromagnetic resonators (cavities) have emerged as a powerful tool for material control, enabling new phases of matter, engineering dynamical processes in cold atoms and altering chemical reaction rates. At the heart of this potentially revolutionary technology lies the fundamental question: to what extent can quantum fluctuations of light be leveraged to control static and dynamical properties of many-body systems through cavities. The presented research thus ranged from the control of cold atomic gases to the manipulating of emerging orders in quantum materials, and from the microwave and terahertz cavities to x-rays. Despite these vastly distinct research areas, common topics of interest were identified and discussed fruitfully. Examples include identifying new avenues of material control using quantum light, elucidating novel physical phenomena unlocked in light-matter hybrid experiments and unveiling applications of cavities to quantum technologies.