Seminarium Fizyki Materii Skondensowanej

This talk will highlight non-trivial effects induced by a photonic environment on the Dirac polaritons that exist in a honeycomb array of meta-atoms embedded in a planar cavtity. In addition to the conventional Dirac points arising due to the matter symmetries, the photonic environment generates additional satellite Dirac points with ∓π Berry flux. Reducing the cavity height induces the merging of the satellite Dirac points with the conventional ones, forming a quadratic band-degeneracy with combined ∓2π Berry flux. As a result, the massless Dirac polaritons with a linear spectrum morph into massive ones with a parabolic spectrum. Remarkably, this merging is not followed by Dirac point annihilation, but instead, massless Dirac polaritons re-emerge with an unprecedented inversion of chirality which has no analog in real or artificial graphene systems. This novel tunability could open up a new realm of unexplored Dirac-related physics, such as unconventional tunnelling and pseudo-magnetic related phenomena, in readily realizable experimental set-ups.