Low-threshold and narrow-linewidth lasing from dye-doped holographic polymer-dispersed liquid crystal transmission gratings

Optically pumped lasing with low threshold and narrow linewidth was observed in a 4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran dye-doped holographic polymer-dispersed liquid crystal transmission grating structure. The results showed that the lasing peak centered at about 609 nm, with a full width at half maximum of about only 1.8 nm. The threshold pumping intensity was about 120 mu J under the excitation of a frequency-doubled Nd:yttrium-aluminum-garnet laser operating at a wavelength of 532 nm. Theoretical calculation showed that the lasing from this structure happened at the band edge of the photonic band gap. The lasing modes were also investigated. The transmission grating investigated enjoys a much larger gain length compared to the reflection one. (c) 2006 American Institute of Physics.