Suppressing Nonradiative Processes of Organic Dye with Metal-Organic Framework Encapsulation toward Near-Infrared Solid-State Microlasers.

Organic materials are an important class of gain media for fabricating miniaturized lasers because they combine fabrication simplicity with wide spectral coverage and tunability. However, progress toward near-infrared (NIR) organic solid-state lasers has been limited because of serious nonradiative processes originating from the severe intermolecular interaction in the condensed state. Here, we develop a strategy to realize room-temperature NIR microscale lasers through encapsulating organic dyes into the cavities of metal-organic frameworks (MOFs). The spatial confinement of the dye molecules within the MOF pores contributes to suppressing the multiple nonradiative processes (i.e., aggregation-caused quenching and exciton-exciton annihilation). This results in a much higher radiative efficiency and thus much easier population inversion and low-threshold NIR lasing. Furthermore, the lasing wavelength can be further expanded based on the tailorable energy levels of the dye molecules. The results will provide useful enlightenment for the development of miniaturized NIR laser sources for new photonic applications.