Room‐Temperature Superfluorescence From Solid‐State Materials

ABSTRACT Superfluorescence (SF) is an exceptional cooperative optical phenomenon that has attracted enduring interest in quantum optics. Historically, the observation of SF has been restricted to extreme conditions, such as cryogenic temperatures or high magnetic fields, owing to the fragility of macroscopic quantum coherence and high dephasing rates, particularly in solid‐state systems. Recent advances in nanoscience and cutting‐edge instrumentation, however, have enabled the realization of room‐temperature SF (RT‐SF) in solid‐state matrices, including hybrid perovskite thin films, lanthanide‐doped upconversion nanoparticles, and quantum dot‐based mesocrystalline superlattices. These breakthroughs overcome long‐standing limitations and open new avenues for exploring SF under ambient conditions. In this context, a deeper understanding of the underlying physical mechanism is essential to guide material design, optimize performance, and enable practical applications. This review highlights the very recent progress in RT‐SF within solid‐state materials, focusing on the photophysical principles and optical signatures that define the phenomenon. Key aspects discussed include the establishment of dipole−dipole correlations, dominant dephasing processes, prerequisites for achieving RT‐SF, and unique emission features. We also outline current challenges and future directions aimed at harnessing the full potential of such an intriguing quantum optical effect.