Light-matter interaction in quantum materials

In this project we will address the behaviour of many-body systems embedded in (optical and microwave) cavities. Investigations will focus in particular on strongly correlated and quantum ordered 2D systems. The presence of a cavity enables reaching the ultra-strong limit of light-matter interaction, which can in turn lead to the emergence of novel quantum phases of matter. The field has recently emerged as a hot topic, with more and more papers (in particular experimental ones) being published on the control of quantum phases realised in van der Waals materials. Intriguingly, the form acquired by such phases can depend on the gauge chosen for the electromagnetic radiation. This fact has been recently studied for model systems such as ensembles of dipoles or continuous (jellium) models. However, no attempt has been made at investigating this physics in realistic models of materials, which will be the focus of this project.