首页 -> 登录 -> 注册 -> 回复主题 -> 发表主题
光行天下 -> MATLAB,SCILAB,Octave,Spyder -> 求解光孤子或超短脉冲耦合方程的Matlab程序 [点此返回论坛查看本帖完整版本] [打印本页]

tianmen 2011-06-12 18:33

求解光孤子或超短脉冲耦合方程的Matlab程序

计算脉冲在非线性耦合器中演化的Matlab 程序 rQEi/  
HmExfW  
%  This Matlab script file solves the coupled nonlinear Schrodinger equations of z Bt`L,^  
%  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of D#7_T KX  
%  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear T;!ukGoFP  
%   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 90s;/y(  
RxZm/:yuJ.  
%fid=fopen('e21.dat','w'); 1s`)yu^`v  
N = 128;                       % Number of Fourier modes (Time domain sampling points) JzMZB"Z?  
M1 =3000;              % Total number of space steps @8nLQh^  
J =100;                % Steps between output of space >+ ]R4  
T =10;                  % length of time windows:T*T0 B:-U`CHHQ  
T0=0.1;                 % input pulse width \2Og>{"U  
MN1=0;                 % initial value for the space output location uuSR%KK]|  
dt = T/N;                      % time step Y}LLOj@L  
n = [-N/2:1:N/2-1]';           % Index @Y UY9+D&  
t = n.*dt;   :p<kQ4   
u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 't( }Rq@  
u20=u10.*0.0;                  % input to waveguide 2 5g``30:o  
u1=u10; u2=u20;                 'j,oIqx  
U1 = u1;   d(fPECv(  
U2 = u2;                       % Compute initial condition; save it in U qO-C%p [5  
ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. o\ngR\>  
w=2*pi*n./T; R-pH Quu3  
g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T '@TI48 J+  
L=4;                           % length of evoluation to compare with S. Trillo's paper qL| 5-(P  
dz=L/M1;                       % space step, make sure nonlinear<0.05 JI"/N`-?;b  
for m1 = 1:1:M1                                    % Start space evolution ~uI**{  
   u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS tAqA^f*{  
   u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; #JA}LA"l  
   ca1 = fftshift(fft(u1));                        % Take Fourier transform zF5q=9 4$  
   ca2 = fftshift(fft(u2)); ja[OcR-tX  
   c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation 1")FWN_K/T  
   c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   mG)8U{L  
   u2 = ifft(fftshift(c2));                        % Return to physical space Di*]ab  
   u1 = ifft(fftshift(c1)); bD35JG^&i  
if rem(m1,J) == 0                                 % Save output every J steps. pkXv.D`  
    U1 = [U1 u1];                                  % put solutions in U array 6&89~W{  
    U2=[U2 u2]; A&?}w_|9  
    MN1=[MN1 m1]; GQN98Y+h  
    z1=dz*MN1';                                    % output location +z\\VD  
  end Lt1U+o[ot  
end 4\M8BRuE  
hg=abs(U1').*abs(U1');                             % for data write to excel n]+.  
ha=[z1 hg];                                        % for data write to excel BhKO_wQ?:J  
t1=[0 t']; +YTx   
hh=[t1' ha'];                                      % for data write to excel file ^7uX$  
%dlmwrite('aa',hh,'\t');                           % save data in the excel format <cYp~e%xIw  
figure(1) a3q\<"|  
waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn JO2xT#V  
figure(2) Is13:  
waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn AD]e0_E  
Dl%?OG<  
非线性超快脉冲耦合的数值方法的Matlab程序 u4YM^* S.  
k oM]S+1  
在研究脉冲在非线性耦合器中的演变时,我们需要求解非线性偏微分方程组。在如下的论文中,我们提出了一种简洁的数值方法。 这里我们提供给大家用Matlab编写的计算程序。   2FGx _ Y  
Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 s~^*+kq  
rvic%bsk  
a/~29gW8E\  
B{p4G`$i1  
%  This Matlab script file solves the nonlinear Schrodinger equations *Bs^NU.  
%  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of EX:{EmaT  
%  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear !z MDP/V  
%  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 #{x5L^v>]  
3 >|uF  
C=1;                           vM`7s[oAK  
M1=120,                       % integer for amplitude >AG^fUArH  
M3=5000;                      % integer for length of coupler (/K5!qh  
N = 512;                      % Number of Fourier modes (Time domain sampling points) @EHIp{0.  
dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. as r=m{C"  
T =40;                        % length of time:T*T0. vX+.e1m  
dt = T/N;                     % time step WL l_'2h  
n = [-N/2:1:N/2-1]';          % Index &~#iIk~%  
t = n.*dt;   :a.0he s  
ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. mc ZGg;3  
w=2*pi*n./T; /b#q*x-b  
g1=-i*ww./2; txq~+'A:+  
g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; rB%y6P B  
g3=-i*ww./2; 5Z{_m;I.   
P1=0; R"+wih  
P2=0; 6NX3"i0 eT  
P3=1; \D?:J3H*]  
P=0; +TN^NE  
for m1=1:M1                 %/T7Z; d  
p=0.032*m1;                %input amplitude =i>\2J%'R  
s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1  sTkkM9  
s1=s10; l~J*' m2  
s20=0.*s10;                %input in waveguide 2 \9)#l#m  
s30=0.*s10;                %input in waveguide 3 L-\ =J  
s2=s20; Zu21L3  
s3=s30; 5& !'^!  
p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   #cU^U#;=r  
%energy in waveguide 1 C>X|VP |C  
p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   k4{:9zL1#?  
%energy in waveguide 2 YEv Lhh  
p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   S~)w\(r  
%energy in waveguide 3 5mgHlsDzu  
for m3 = 1:1:M3                                    % Start space evolution Ei5wel6!  
   s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS mS%4gx~~_n  
   s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; r_U>VT^E:  
   s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; Izo!rC  
   sca1 = fftshift(fft(s1));                       % Take Fourier transform cin2>3Z$  
   sca2 = fftshift(fft(s2)); CzVmNy)kl  
   sca3 = fftshift(fft(s3)); -M4p\6)Ge  
   sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   + E5=$`  
   sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); ?6P.b6m}0  
   sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); a1c1k}  
   s3 = ifft(fftshift(sc3)); W7=V{}b+  
   s2 = ifft(fftshift(sc2));                       % Return to physical space cozXb$bBY  
   s1 = ifft(fftshift(sc1)); E0l _--  
end gR Nv-^  
   p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); ~R]35Cp-#  
   p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); )TJS4?  
   p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1))));  8=;k"  
   P1=[P1 p1/p10]; WE6\dhJ<  
   P2=[P2 p2/p10]; 4=[7Em?oLb  
   P3=[P3 p3/p10]; t'1Y@e  
   P=[P p*p]; {f DTSr?/  
end E(^0B(JF  
figure(1) H?`g!cX  
plot(P,P1, P,P2, P,P3); aeP[+I9  
edvFQ#,d  
转自:http://blog.163.com/opto_wang/
ciomplj 2014-06-22 22:57
谢谢哈~!~
查看本帖完整版本: [-- 求解光孤子或超短脉冲耦合方程的Matlab程序 --] [-- top --]

Copyright © 2005-2025 光行天下 蜀ICP备06003254号-1 网站统计