Re: Help: inverse shell opal

On May 17, 2010, at 11:52 AM, Clark Lee wrote:
> I wish to calculate the band diagram of a overlapping titania shell  
> hollow model ( inverse opal). I wonder my calculation is correct  
> since the result is different from the transmission spectra:

1) Make sure you output the epsilon.h5 file and look at it (see the  
data visualization tutorial).  It is easy to have a typo in your  
geometry that you don't notice unless you actually visualize the  
structure to make sure it is what you want.

2) Especially if the transmission spectrum is normal incidence, it can  
have many dips that aren't complete gaps.  You have to look for gaps  
in the bands corresponding to the direction of incidence, and  
furthermore you should look at the symmetry of the bands in case there  
are some that have the wrong symmetry to couple to a normal-incident  
planewave source (which is even with respect to the axis of  
polarization and odd with respect to the axis perpendicular to the  
polarization).

Steven