切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9417阅读
    • 1回复

    [分享]求解光孤子或超短脉冲耦合方程的Matlab程序 [复制链接]

    上一主题 下一主题
    离线tianmen
     
    发帖
    58
    光币
    15
    光券
    0
    只看楼主 正序阅读 楼主  发表于: 2011-06-12
    计算脉冲在非线性耦合器中演化的Matlab 程序 _;J9q}X  
    CyK$XDHa  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of Io4:$w  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of {YKMQI^O/  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear PgG |7='  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 T956L'.+G  
    &x0TnW"g  
    %fid=fopen('e21.dat','w'); }N#>q.M  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) OJ_2z|f<  
    M1 =3000;              % Total number of space steps CI~;B  
    J =100;                % Steps between output of space {Y* ]Qc  
    T =10;                  % length of time windows:T*T0 WKrZTPD'm  
    T0=0.1;                 % input pulse width Nh\8+v*+{  
    MN1=0;                 % initial value for the space output location fD#&:)  
    dt = T/N;                      % time step U3 8wGSG  
    n = [-N/2:1:N/2-1]';           % Index YqY6\ mo  
    t = n.*dt;   kX ,FQG>  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 d-N"mI-  
    u20=u10.*0.0;                  % input to waveguide 2 @+CSY-g$  
    u1=u10; u2=u20;                 Q@ )rw0$  
    U1 = u1;   1=q?#PQ  
    U2 = u2;                       % Compute initial condition; save it in U M%5$-;6~_  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. WtdkA Sj  
    w=2*pi*n./T; oCdOC5  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T M(h H#_ $  
    L=4;                           % length of evoluation to compare with S. Trillo's paper W$t}3Ru  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 wM4g1H%s  
    for m1 = 1:1:M1                                    % Start space evolution k>0cTBY&  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS rIFC#Jd/  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; DN 8pJa  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform V\M!]Nnxr  
       ca2 = fftshift(fft(u2)); V+a%,sI  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation '3u]-GU2_  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   pTX'5   
       u2 = ifft(fftshift(c2));                        % Return to physical space @H# kvYWmn  
       u1 = ifft(fftshift(c1)); ep}/dBg  
    if rem(m1,J) == 0                                 % Save output every J steps. \lbiz4^>  
        U1 = [U1 u1];                                  % put solutions in U array K!: ,l  
        U2=[U2 u2]; g/X=#!  
        MN1=[MN1 m1]; ~Ro:mH: w  
        z1=dz*MN1';                                    % output location w%o4MFK=!  
      end NdSxWrD`m  
    end uF3p1by  
    hg=abs(U1').*abs(U1');                             % for data write to excel 5B.??;xtaV  
    ha=[z1 hg];                                        % for data write to excel ])wMUJWg2  
    t1=[0 t']; ]o+|jgkt]  
    hh=[t1' ha'];                                      % for data write to excel file 9]F&Fz/G  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format yg[;  
    figure(1) @[b:([  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn MqBATW.pmJ  
    figure(2) OYtus7q<  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn y yR8VO{  
    5WJkeG ba  
    非线性超快脉冲耦合的数值方法的Matlab程序 !g&B)0u]*  
    *,[=}v1  
    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。   iCSM1W3  
    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 %^%-h}1  
    >T*g'954xF  
    rnhf(K.{3  
    VaI P  
    %  This Matlab script file solves the nonlinear Schrodinger equations Q fyERa\rb  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of KP7RrgOan&  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear DPxu3,Y  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 &?`&X=Q  
    IC-xCzR  
    C=1;                            ;yER V  
    M1=120,                       % integer for amplitude fh)`kZDk  
    M3=5000;                      % integer for length of coupler @?=)}2=|?i  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) x7 1!r  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. 2P=~3g*  
    T =40;                        % length of time:T*T0. %=<NqINM[  
    dt = T/N;                     % time step q4ko}jn  
    n = [-N/2:1:N/2-1]';          % Index _r5Ild @n  
    t = n.*dt;   ?~Ed n-" Y  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. "l,EcZRjTz  
    w=2*pi*n./T; h_G7T1;L  
    g1=-i*ww./2; eC`f8=V  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; <({eOh5 N  
    g3=-i*ww./2; rtF6Lg  
    P1=0; nkj'AH"2  
    P2=0; j<P%Uy+  
    P3=1; hJ*E"{xs  
    P=0; bNU^tL3QZ  
    for m1=1:M1                 yaYt/?|  
    p=0.032*m1;                %input amplitude L0VR(  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 v 4b`19}  
    s1=s10; HPdwx V  
    s20=0.*s10;                %input in waveguide 2 E=*Q\3G~  
    s30=0.*s10;                %input in waveguide 3 i@^`~vj  
    s2=s20; (*Q|;  
    s3=s30; [f(^vlK  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   c@B%`6kF  
    %energy in waveguide 1 .u;TeP  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   K y2xWd8  
    %energy in waveguide 2 OjEA;;qq  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   t-(7Q8(  
    %energy in waveguide 3 _NnO mwK7  
    for m3 = 1:1:M3                                    % Start space evolution }t-|^mY>  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS +i!M[  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; 0_pwY=P  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; W1`ZS*12D  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform qm5pEort  
       sca2 = fftshift(fft(s2)); 3D dG$@  
       sca3 = fftshift(fft(s3)); [ =2In;  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   Df3v"iCq}  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); 2U+p@}cQUA  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); r3vj o(  
       s3 = ifft(fftshift(sc3)); $rYu4^  
       s2 = ifft(fftshift(sc2));                       % Return to physical space J5IJy3d  
       s1 = ifft(fftshift(sc1)); -XG$ 0  
    end z))[Lg  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); OBSJbDqT  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); bK1`a{  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); @}!$NI8  
       P1=[P1 p1/p10]; qM !q,Q  
       P2=[P2 p2/p10]; \^LR5S&  
       P3=[P3 p3/p10]; Ud*[2Oi|R  
       P=[P p*p]; 8|Y^Jn\p5u  
    end *bSG48W("  
    figure(1) K3D $ hb  
    plot(P,P1, P,P2, P,P3); G_mu7w  
    P`9A?aG.Z  
    转自:http://blog.163.com/opto_wang/
     
    分享到
    离线ciomplj
    发帖
    319
    光币
    1
    光券
    0
    只看该作者 1楼 发表于: 2014-06-22
    谢谢哈~!~