We investigate the behavior of polariton transport due to the influence of the photonic character of the initial wave packet at t = 0. We consider λ = 36 meV, and Q = 633 (which is in line with the cavity used in Ref. 1), and a narrow band of initial excitation conditions with a narrow range of k ∥ on the LP state (see Fig. ), to model the kselective probing conditions in Ref. 3