Interacting Photons

Free-space photons are ideal information-carriers. However, they do not mutually interact and this limits our ability to control light with light. This limitation can be circumvented by strongly coupling photons to interacting quasi-particles such as excitons. The emergent hybrid light-matter quasi-particles, known as polaritons, mutually interact and give rise to a nonlinear response. In this sense, polariton systems enable effective photon-photon interactions.

In the Interacting Photons group, we harness photon-photon interactions to investigate phenomena emerging from the interplay of optical nonlinearity and noise. We use organic and inorganic nanostructured materials combined with open-access microcavities enabling fine control over the exciton-photon coupling. Our fundamental interests include critical phenomena (out-of-equilibrium phase transitions), noise-assisted photon transport in driven-dissipative systems, and quantum simulation. We are also interested in applications of interacting photonic systems, e.g. optical memories, switches, and quantum networks.

Figure 1.  This figure shows how we can couple photons in open-access microcavities with excitons in active materials to create hybrid light-matter quasi-particles known as polaritons.  The excitonic constituent confers polaritons giant interaction strengths, while the photonic constituent enables micron-scale confinement of polaritons followed by photon emission. Hence, polaritons constitute an excellent system for studying light-matter interactions under the influence of tunable interactions, driving, dissipation. Figure credit to Henk-Jan Boluijt, AMOLF.