In this seminar, I will present and discuss recent results from one of the experimental research lines at Hafezi group: quantum Hall physics in semiconductor microcavities. A 2D charge gas (2DCG) operating in the quantum Hall regime represents one of the few examples of macroscopic quantum behavior. Other examples in this short list are Bose-Einstein condensation and superconductivity. Typically, the experimental study of the quantum Hall effect relies on transport. Another possibility is to optically probe the 2DCG, which provides the advantage of more local measurements. Physics becomes even richer when the gas is strongly coupled to a microcavity mode, giving origin to polaritonic states influenced by quantum Hall physics. This is the system I will focus on in this talk. I will discuss the demonstration of a mechanism to induce spin-selective strong light-matter coupling by exploiting the interplay between Zeeman splitting and the modification of the density of states induced by an external magnetic field. This demonstration provides a tool to induce chiral behavior in light-matter hybrid systems and opens perspectives to control the nonlinearity in polaritonic systems.

(Pizza and refreshments will be served after the talk.)