The Theoretical Investigation of Superfluorescent Phase Transition in Lead-Halide Perovskites

Lead halide perovskites exhibit room temperature superfluorescence above certain critical exciton density/excitation fluence. Our analysis shows that rotational modes of lattice deformation strongly couple to excitons to create exciton-polarons with long lifetimes. To establish the theoretical grounds of this observation, we developed a continuum field theory for such interactions. We showed that above a certain critical threshold, the polarons can form a soliton state which is a lower energy configuration. This creates a coherent population of excitons strongly coupled to a common lattice frequency. Our field theory model also lays out a theoretical framework for the Quantum Analog of Vibration Isolation (QAVI) hypothesis for achieving high-temperature quantum coherence in solid-state systems.