Ultra-strong trion-polaritons

Due to the hybridization of charged excitons with cavity photons, trion-polaritons (TP) in microcavity semiconductors are a promising avenue for realizing strong polariton interactions and many-body polariton phases. We develop a quantum field theoretical formalism to study the formation of trion-polaritons in a microcavity semiconductor doped with itinerant electrons within the ultra-strong light-matter coupling regime. We predict a new class of many-body states resulting from the intriguing interplay of polarons and virtual photons in an uncharted territory of light-matter interactions and Feshbach physics.