White-light laser based on an organo-inorganic photonic structure

Photo-stimulated laser based on photonic crystals usually has either one of the two different lasing modes, the bandedge-mode or the defect-mode. This study demonstrates both lasing modes can coexist in a single organo-inorganic photonic (OIP) structure. The OIP is composed of a layer of dye-doped cholesteric liquid crystal (DDCLC) infiltrated in between two photonic crystals made of a specific sequence of dielectric multilayer. Through this delicately designed device, a white-light equivalent laser source can be produced with a single pumping light. The white-light color is discretely mixed of three primary colors which generated from one defectmode and both sides of band edge-mode lasing. Since the DDCLC can be regulated by applying voltage across, the OIP composite device has the electrical tunability in lasing wavelength. The bistability of CLC further provides an addition benefit of energy-saving. Besides of all the above features, the OIP device is also a low-cost and readily feasible white-light laser source.