Lasing in Dye–Doped Photonic Liquid Crystal Devices

Abstract

We have investigated the effects of pumping laser's polarization and incident angles, dye concentration, cell gap, and lasing wavelength on the lasing efficiency of the dye doped cholesteric liquid crystal (CLC) devices. These factors impact the lasing efficiency due to the existence of the photon bleaching and quench in the dye molecules, the competition of the optical gain and loss in the media, and the helical layers dependent amplification provided by the distributed feedback. The maximum lasing efficiency (∼ 0.5%) was obtained at λ ∼ 608 nm from a 10 µm CLC sample doped with 1 wt% DCM when the pump laser beam is left-handed circularly polarized and the incident angle is normal to the sample.