  A general coupled-wave model is presented for square-lattice photonic crystal
(PC) lasers with transverse-electric polarization. This model incorporates the
high-order coupling effects that are important for two-dimensional PC laser
cavities and gives a general and rigorous coupled-wave formulation for the full
three-dimensional structures of typical laser devices. Numerical examples based
on our model are presented for PC structures with different air-hole shapes.
The accuracy of the results obtained is verified using three-dimensional
finite-difference time-domain simulations.
