Strong light–matter interaction in organic microcavity polaritons: essential criteria, design principles and typical configurations

Resonant light–matter interaction between a molecular transition and a confined electromagnetic field can result in strong coupling where a coherent exchange of energy between light and matter occurs to form a new set of particles called polaritons. Being hybrid particles, polaritons exhibit a wide variety of quantum phenomena such as Bose–Einstein condensation, superfluidity, quantum phase transitions and many others. Recent progress in fundamental understanding and technological advancement in the field of polariton physics has allowed scientists to design and develop many impressive experimental configurations to obtain new insights into the strong interaction of light and matter in different material systems. Among all polariton configurations, microcavity polaritons based on organic materials have been emerging as a promising platform to easily achieve strong light–matter coupling at ambient conditions due to their unique properties compared to the conventional inorganic polariton systems. This mini review covers design principles and typical configurations of organic microcavity polaritons with a short tutorial on essential conditions to be satisfied for the strong coupling regime.