Effect of Phase Retardation on Defect-Mode Lasing in Polymeric Cholesteric Liquid Crystals

The authors studied the effects of an anisotropic nematic liq, crystal (NLC) defect layer introduced between polymeric cholesteric liq. crystals (PCLC) layers. It was found that the modulation of reflectance exceeds the 50 % limitation provided by simple CLC photonic bandgap (PBGs) due to the birefringence of the defect layer. Moreover, by adjusting the PBG region to be coincident with the fluorescent emission band for the guest polymer dye, sharp defect-mode lasing was obsd. successfully at the defect mode in the middle of PBG. From these results, it was demonstrated that the configuration of a PCLC with a polymer-dye-doped anisotropic defect layer is very attractive for lasing. [on SciFinder(R)]