On Sun, 20 Aug 2006, hlren wrote:
This is 2D triangular lattice photonic crystal with air holes in GaAs
substrate. The backgound dielectric index is 11.4. We calculalte the
dispersion relations of line defect waveguides filled with liquid
crystal, and the attached file is about the supercell, and Dark and
light shaded regions indicate GaAs and liquid crystals, respectively.
When the rotation angle of the director of the liquid crystal is 90¡ã,
the components of the dielectric tensor are ne*ne,no*no,and zero in xx
,yy, and xy directions,respectively, where ne is 1.706 ,and no is 1.522
( this direction is in accord with that in the supercell). I try some
examples about liquid crystals, and the problem is also present. Would
you mind scanning my ctl file?
When you specify the dielectric tensor, you are specifying it in Cartesian
coordinates. This is not the same as the lattice basis. So, in your case
where the Cartesian x direction is *not* the direction of your waveguide.
This means that the principal axes of your dielectric tensor are not
aligned with your waveguide like you probably want.
Cordially,
Steven G. Johnson
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