Ultrafast Optical Properties of Cavity‐Enhanced Superfluorescence.

Cavity‐enhanced superfluorescence is an ultrafast and intense lasing produced by strong interaction between superfluorescence and optical cavity. However, due to the quite difficulty of particle cooperative emission in solid‐state systems, and the low coupling efficiency between superfluorescence and optical cavity, research on ultrafast optical properties of cavity‐enhanced superfluorescence is thus far in its infancy. Fortunately, perovskites being made into quantum dot superlattice microcavity is an excellent candidate as such light source. This work reveals the time‐dependent redshift process of cavity‐enhanced superfluorescence under high‐power injection, and interprets the physical mechanism of lasing broadening with increasing power from the dynamic perspective. At the same time, the multi‐mode lasing dynamic photoluminescence image output at different times is also tracked. The short‐wavelength resonance mode has a lower stimulated threshold, but its radiation lags behind the long‐wavelength resonance mode by 4 ps in high excited density. These ultrafast optical property researches may promote the application of quantum dot superlattices in information technology, optical communications, ultrafast lasers, and other fields. [ABSTRACT FROM AUTHOR]