An Optically Reconfigurable Förster Resonance Energy Transfer Process for Broadband Switchable Organic Single-Mode Microlasers

Miniaturized lasers with multicolor output and high spectral purity are indispensable for various ultracompact photonic devices. Here, we propose an optically reconfigurable Förster resonance energy transfer (FRET) process to realize broadband switchable single-mode lasing based on in situ activation of acceptors. The stoichiometric ratio of the donor and acceptor in the ready-made microstructures could be modulated readily by precisely activating the acceptors through a photoisomerization process, leading to a reconstructed FRET process to achieve dynamically switchable lasing. Furthermore, dual-color switchable single-mode lasing was realized by selectively constructing the FRET process in an identical coupled microdisks system. These results advance a comprehensive understanding of excited-state dynamics in organic composite material systems, thereby providing new ideas for the rational design of miniaturized photonic materials and devices with desired performances.