Color cone lasing emission in a dye-doped cholesteric liquid crystal with a single pitch

This work investigates a novel color cone lasing emission (CCLE) based on a one-dimensional photonic crystal-like dye-doped cholesteric liquid crystal (DDCLC) film with a single pitch. The lasing wavelength in the CCLE is distributed continuously at 676.7-595.6 nm, as measured at a continuously increasing oblique angle relative to the helical axis of 0-50 degrees. This work demonstrates that lasing wavelength coincides exactly with the wavelength at the long wavelength edge of the CLC reflection band at oblique angles of 0-50. Simulation results of dispersion relations at different oblique angles using Berreman's 4x4 matrix method agrees closely with experimental results. Some unique and important features of the CCLE are identified and discussed. (C) 2009 Optical Society of America