Eigenmodes in a 2D photonic crystal

Solves the eigenproblem kz(omega,kx,ky) and plots the field distributions for allowed modes

consider a 2D photonic crystal consisting of cylinders with circular cross-section and infinite height, arranged in a triangular lattice;
this program calculates and plots the spatial distributions in the unit cell (E&H) of eigenmodes allowed at a given frequency ; 'omega'is taken as input; oblique propagation is implicit, so the polarization states cannot be separated in E-pol and H-pol;
Fourier coefficients for the expansion of dielectric constant are calculated analytically;
the materials considered here are dielectric and dispersionless;

the package contains the following programs:
pwem2Dc.m - main program
epsgg.m - routine for calculating the matrix of Fourier coefficients of dielectric function
prcellgrid.m - routine for discretization of direct space, to be used for plotting the field distribution
kvect2.m - routine for calculating diagonal matrices with elements (kx+Gx) and (ky+Gy), where G=(Gx,Gy) is a reciprocal lattice vector
oblic_eigs.m - routine for solving the eigenvalue problem for
H-field
rfields.m - routine for calculation of field spatial distributions