Where are the resonant modes (at what wavelength) of a 2D photonic
crystal microcavity?  The necessary device information is:

material: GaAs
lattice:  square
lattice constant: 300 nm
filling fraction (radius/lattice constant): 0.38

The device is a slab of GaAs that is 180 nm thick, with air above and
below it (this membrane is suspended in air and supported on its
perimeter).  A photonic crystal of the parameters mentioned above is
etched into the slab.  The cavity is formed by removing four holes
from the photonic crystal.  There are ten lattice periods in all
directions from the cavity.

Thanks!

I'm looking for answers of the folling form:

"mode number 1 -- type: dipole, wavelength: 950 nm, quality factor:
1000"

Not my cup of tea, but there is a decent doctoral thesis that might be
beneficial although the parameters differ from those stated.
Maxwell constants and Einstein's coefficient tend to give me
indigestion, so I'll not even venture further in this topic. My
sliderule is oxidized anyway.

A google search on key words like "photonic crystal microcavity"
+dipole +lattice constant +300nm will get you a few sites that might
assist in your computations.

"Modification of spontaneous emission in photonic crystals"

http://216.239.35.100/search?q=cache:pnjYP0hsy9sC:www.ee.ucla.edu/labs/photon/thesis/ThesisMisha.pdf+Modification+of+spontaneous+emission+&hl=en&ie=UTF-8

://www.google.com/search?sourceid=navclient&q=Modification+of+spontaneous+emission+