runfft.m

一组很好的FDTD计算二维光子带隙的程序

function RunFFT

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Electromagnetic Finite-Difference Time-Domain %
% Version 1.20, Release 1                       %
%                                               %
%   (C) Copyright 2005                          %
%   Sharif University of Technology             %
%   School of Electrical Engineering            %
%   All Rights Reserved                         %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

global U dT TimeDecimation LatticeCnt
global Peaks wrng

LoadField;

fftU=fft(U);
P=fftU.*conj(fftU);
L=length(fftU);

wstep=LatticeCnt/(L-1);
wrng=0:wstep:LatticeCnt;

Peaks=PeakDetect(wrng,P)/dT/TimeDecimation;