Tailoring the polariton dispersion by optical confinement: Access to a manifold of elastic polariton pair scattering channels

Abstract

Angle-resolved spectroscopy of wire-shaped microcavities in the strong coupling regime is used to demonstrate elastic polariton pair scattering. Due to the lateral confinement of the light field each of the polariton modes of a planar cavity splits into a multiplet of subbranches. The polariton mode fan gives access to a variety of channels for polariton pair scattering. Parametric scattering among branches of the lower polariton multiplet is realized as well as processes involving the upper polariton modes. In the scattering events signal and idler state have to be located in subbranches with identical symmetry to conserve parity. This constraint adds to the requirements of energy and momentum conservation.