On Thu, 2 Nov 2006, Ngo Quang Minh wrote:
I would like to compute the defect modes (Resonant frequencies) in photonic crystal slab. (According to the document of MPB User tutorial - Finding a point defect state). I do not understand what my .ctl file is wrong!
You have a fundamental problem: finding the resonant modes in a slab is a completely different problem from finding the defect mode in a 2d crystal with a complete 2d gap. It looks like you think you can analyze this just like a 2d crystal, but that is not the case.
A photonic-crystal slab does *not* have a complete gap (there are extended, light-cone modes at every frequency), and so there is no exponentially localized point-defect mode. This makes periodic boundary conditions problematic (in principle, if you look at all the modes of the periodic cell, including the supercell wavevector, you will see a resonant peak in the mode amplitude around the resonant frequency...but in practice this kind of computation is a bit painful).
Furthermore, the targeted solver has no chance of working because there are light-cone modes in addition to resonant modes inside the gap.
For point-defect resonant modes in slabs you are probably better off using our time-domain code, Meep, which can impose absorbing boundary conditions and compute the resonant frequency and lifetime.
Steven _______________________________________________ mpb-discuss mailing list [email protected] http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
