Anisotropic waveguide theory for electrically tunable distributed feedback laser from dye-doped holographic polymer dispersed liquid crystal

摘要

Anisotropic waveguide theory is developed for electrically tunable distributed feedback (DFB) laser from dyedoped holographic polymer dispersed liquid crystal (HPDLC) grating. The period grating structure, optical anisotropy of the liquid crystal (LC) and practical light propagation path in the HPDLC have been considered. The emitted lasing wavelength is deduced on basis of the dielectric anisotropy of the LC, transverse-magnetic (TM) light wave propagation in the core layer and DFB laser theory. An experimental method to determine the tilt angle of the LC and the lasing behaviours under different electric fields are used to verify the validity of the anisotropic numerical analysis. The results show that a more accurate agreement between the theoretical calculations and the experimental data is achieved. The anisotropic numerical analysis presented here is very useful when designing and optimising tunable lasers for optical communications and integrated optics.