  The transmission and reflection spectra from a right-handed chiral sculptured
zirconia thin film are calculated using the coupled wave theory and the
Bruggeman homogenization formalism in conjunction with the experimental data
for the relative dielectric constant of zirconia thin film. The dielectric
dispersion function effect on these spectra appeared in wavelengths shorter
than the Bragg wavelength. In wavelengths larger than the Bragg wavelength, the
dispersion of the dielectric function can be ignored. The results achieved in
this work are consistent with the experimental data (Wu et al. (2000)). A shift
towards shorter wavelengths is observed for the Bragg peak with increasing the
void fraction, which is in agreement with the theoretical work of Lakhtakia
(2000). Sorge et al. (2006) also found this effect in their experimental
results on TiO2 chiral thin films, while they also found that unlike our
results the intensity of the reflectance of the Bragg peak decreases with
increasing the void fraction. This difference between our theoretical work and
Sorge et al. (2006) experimental work can be related to the structural
difference between idealized theoretical model for chiral films and that
obtained in experimental work. In the latter, as Sorge et al. (2006) have
pointed out the experimental films exhibit a large amount of scattering due to
the highly complex and non-ideal structure that the individual chiral elements
exhibit.
