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 #~-&&S4a.J  
J8?6G&0H  
%  This Matlab script file solves the coupled nonlinear Schrodinger equations of {UC<I.5X  
%  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of qg:I+"u  
%  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear Fl3r!a!P,  
%   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 gsm^{jB  
B|$13dHfa  
%fid=fopen('e21.dat','w'); R$&&kmJ  
N = 128;                       % Number of Fourier modes (Time domain sampling points) #|1QA3KzO  
M1 =3000;              % Total number of space steps B5r_+?=2e  
J =100;                % Steps between output of space ?CZD^>6  
T =10;                  % length of time windows:T*T0 ygY+2  
T0=0.1;                 % input pulse width Qbpl$L  
MN1=0;                 % initial value for the space output location 4lf36K ,  
dt = T/N;                      % time step HV7(6VSJ+  
n = [-N/2:1:N/2-1]';           % Index ^JVP2L>o*  
t = n.*dt;   $$f$$  
u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 +9F#~{v`4a  
u20=u10.*0.0;                  % input to waveguide 2 4S EC4yO  
u1=u10; u2=u20;                 EA E\Xv  
U1 = u1;   }w^ T9OC  
U2 = u2;                       % Compute initial condition; save it in U j/mp.'P1k  
ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. qFChZ+3>  
w=2*pi*n./T; T*~)9o  
g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T VEKITBs  
L=4;                           % length of evoluation to compare with S. Trillo's paper q/-j`'A_pb  
dz=L/M1;                       % space step, make sure nonlinear<0.05 Q~!hr0 ZR  
for m1 = 1:1:M1                                    % Start space evolution et}Y4,:  
   u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS 3C[4!>|  
   u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; FS+^r\)  
   ca1 = fftshift(fft(u1));                        % Take Fourier transform vK7,O%!S  
   ca2 = fftshift(fft(u2)); !Lug5U}  
   c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation z n8ig/C  
   c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   >d V@9  
   u2 = ifft(fftshift(c2));                        % Return to physical space }lpm Hvs  
   u1 = ifft(fftshift(c1)); 24/~gft  
if rem(m1,J) == 0                                 % Save output every J steps. |5B9tjJ"  
    U1 = [U1 u1];                                  % put solutions in U array }V,M0b>  
    U2=[U2 u2]; fQ4$@  
    MN1=[MN1 m1]; -gGK(PIf  
    z1=dz*MN1';                                    % output location j6(IF5MqP  
  end q$'&RG  
end rh&Eu qE%  
hg=abs(U1').*abs(U1');                             % for data write to excel ;rAW3  
ha=[z1 hg];                                        % for data write to excel Y[?Wt/O;  
t1=[0 t']; Cbvl( (  
hh=[t1' ha'];                                      % for data write to excel file H).5xx[`  
%dlmwrite('aa',hh,'\t');                           % save data in the excel format ^uEl QI  
figure(1) gc[J.[  
waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn Cfb-:e$0  
figure(2) gt(nZ  
waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn u$p|hd d  
^O*hs%eO%  
非线性超快脉冲耦合的数值方法的Matlab程序 $%8n,FJ[  
K"$ky,tU  
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。   n(S-F g  
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 x#mk[SV  
Vho0f<`E  
m48Y1'4  
0j MI)aY.  
%  This Matlab script file solves the nonlinear Schrodinger equations 5B/\vLHg4  
%  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of Dy@NgHe  
%  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear )!-'SH  
%  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 9GaER+d|  
cs;Gk:  
C=1;                           xTm&`Xo  
M1=120,                       % integer for amplitude C,u.!g;lm  
M3=5000;                      % integer for length of coupler "T=LHjE  
N = 512;                      % Number of Fourier modes (Time domain sampling points) 4 jro4B`  
dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. 7gaC)j&  
T =40;                        % length of time:T*T0. K L~sEli  
dt = T/N;                     % time step (9|K}IM:  
n = [-N/2:1:N/2-1]';          % Index _>64XUZ<n  
t = n.*dt;   qrh7\`,.m/  
ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. rdg1<Z  
w=2*pi*n./T; imQNfNm  
g1=-i*ww./2; 6I![5j  
g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; t[,\TM^h}0  
g3=-i*ww./2; iO`f{?b  
P1=0; <P- r)=^  
P2=0; N3RwcM9+;  
P3=1; YaNVpLA  
P=0; -.{7;6:(k  
for m1=1:M1                 8;3FTF  
p=0.032*m1;                %input amplitude I =pdjD  
s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 m:CpDxzbf  
s1=s10; gk%ye&:f  
s20=0.*s10;                %input in waveguide 2 R!CUR~F  
s30=0.*s10;                %input in waveguide 3 6 dMpd4"\  
s2=s20; *A`^ C  
s3=s30; $hh=-#J8  
p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   q1Mk_(4oJ  
%energy in waveguide 1 '9XwUQx  
p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   9x< 8(]\  
%energy in waveguide 2 ElxbHQj6  
p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   2c]O Mtk  
%energy in waveguide 3 E;0"1 P|S  
for m3 = 1:1:M3                                    % Start space evolution C?k4<B7V  
   s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS c7_b^7h1  
   s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; uRg^:  
   s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; P6rL;_~e  
   sca1 = fftshift(fft(s1));                       % Take Fourier transform tnntHQ&b  
   sca2 = fftshift(fft(s2)); }e)ltp|  
   sca3 = fftshift(fft(s3)); l[Oxf|  
   sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   u 05O[>w  
   sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); lom4z\6  
   sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); wB{-]\H`\  
   s3 = ifft(fftshift(sc3)); =6:Iv"<  
   s2 = ifft(fftshift(sc2));                       % Return to physical space 4 @h6|=  
   s1 = ifft(fftshift(sc1)); i8F~$6C  
end S1JB]\  
   p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); UPsh Y  
   p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); M Cz3RZK  
   p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); [gDvAtTZ5  
   P1=[P1 p1/p10]; O^GTPYW  
   P2=[P2 p2/p10]; EBm\rM8  
   P3=[P3 p3/p10]; xi0&"?7la  
   P=[P p*p]; +dRTHz  
end pQD8#y)`C  
figure(1) ^z1WPI  
plot(P,P1, P,P2, P,P3); HU'}c*d]  
_G42|lA$/  
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