A numerical scheme for modeling the waveguiding properties of a biased capillary tube infiltrated with nematic liquid crystal is presented. The structure of the liquid crystal under bias is determined by solving the Poisson equation for the electrostatic field and minimizing the elastic free energy of the liquid crystal in a self-consistency procedure. The resulting dielectric tensor is calculated, and the guided modes of the capillary waveguide are found. Results are reported for E7 liquid crystal in a single capillary as well as for a periodic geometry. The influence of the surrounding dielectric structure upon the liquid-crystal structure of an individual capillary tube is found to be minor. The photonic density of states of a square array of biased capillaries is calculated and is found to be highly tunable with respect to both the spectral positions of peaks and bandgaps as well as the widths of the photonic bands.
© 2006 Optical Society of America
Original Manuscript: January 9, 2006
Revised Manuscript: March 14, 2006
Manuscript Accepted: April 6, 2006
Jesper Lægsgaard, "Modeling of a biased liquid-crystal capillary waveguide," J. Opt. Soc. Am. B 23, 1843-1851 (2006)