Abstract
Organic lasers with broad emission bands in near-infrared(NIR)region are crucial for their applications in laser communication,night-vision as well as bioimaging owing to the abundance of selectable lasing wavelengths.However,for most organic gain materials,gain regions are limited in a small wavelength range because of the fixed energy level systems.Herein,we design a strategy to realize NIR organic lasers with broad emission bands based on tunable energy level systems induced by cascaded excited-state intramolecular proton transfer(ESIPT).A novel gain material named DHNN was developed,which can undergo a cascaded double-ESIPT process supporting four-level and six-level systems simultaneously.By doping DHNN into polystyrene microspheres,NIR lasers with tunable emission bands can be achieved based on the careful modulation of microcavities.Finally,organic lasers with an ultra-broad emission band ranging from 700 nm to 900 nm was successfully achieved by harnessing four-level and six-level systems simultaneously.
维普
万方数据