切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9151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 倒序阅读 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 Zlv`yC*r  
    vJQ_mz  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of j,1cb,}=^  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of Vp8!-[R  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear z:08;}t  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 ("=B,%F_  
    n ,@ ge  
    %fid=fopen('e21.dat','w'); 3)l<'~"z<  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) n]K{-C;  
    M1 =3000;              % Total number of space steps 9 vNz yh\  
    J =100;                % Steps between output of space y )7;"3Q<  
    T =10;                  % length of time windows:T*T0 ;v ~xL!uQ  
    T0=0.1;                 % input pulse width Ujvk*~:  
    MN1=0;                 % initial value for the space output location 9"dZ4{\!  
    dt = T/N;                      % time step C-(O*hK  
    n = [-N/2:1:N/2-1]';           % Index 3IoN.  
    t = n.*dt;   h 3p~\%^  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 !6J+#  
    u20=u10.*0.0;                  % input to waveguide 2 * [b~2  
    u1=u10; u2=u20;                 h~#.s*0.F  
    U1 = u1;   :|=Xh"l"  
    U2 = u2;                       % Compute initial condition; save it in U *{=q:E$  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. ]w!=1(  
    w=2*pi*n./T; k[1w] l8  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T }5u;'>$  
    L=4;                           % length of evoluation to compare with S. Trillo's paper = Fwzm^}6  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 "gXvnl  
    for m1 = 1:1:M1                                    % Start space evolution %:Zp7O2UB'  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS tSiQr I  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; ASr3P5/  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform 92^Dn`g  
       ca2 = fftshift(fft(u2)); *C(q{|f  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation XE;aJ'kt  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   l, -q:8  
       u2 = ifft(fftshift(c2));                        % Return to physical space .j`8E^7<  
       u1 = ifft(fftshift(c1)); oN(F$Nvk  
    if rem(m1,J) == 0                                 % Save output every J steps. f/i[? gw  
        U1 = [U1 u1];                                  % put solutions in U array JL?|NV-  
        U2=[U2 u2]; p49T3V  
        MN1=[MN1 m1]; *35o$P46  
        z1=dz*MN1';                                    % output location Bh6lK}9  
      end q/3co86c  
    end N| |s#  
    hg=abs(U1').*abs(U1');                             % for data write to excel }ct*<zj[~u  
    ha=[z1 hg];                                        % for data write to excel ^NO;A=9b[  
    t1=[0 t']; :LD+B1$y  
    hh=[t1' ha'];                                      % for data write to excel file P~@I`r567  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format R)9FXz$).  
    figure(1) 4$4n9`odE  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn Q0TKM >  
    figure(2) 62>/0_m5  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn / gE9 W  
    `R o>?H  
    非线性超快脉冲耦合的数值方法的Matlab程序 {ALOs^_-  
    |bjLmGb  
    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。   w%f51Ex  
    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 oX[I4i%G  
    V(n3W=#kky  
    E>qehs,g  
    `wNJ*`  
    %  This Matlab script file solves the nonlinear Schrodinger equations OC2%9Igx0  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of suZ`  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear [,mcvO;  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 $I90KQB\_  
    t Ow[  
    C=1;                           "QV1G'  
    M1=120,                       % integer for amplitude Bqb3[^;~  
    M3=5000;                      % integer for length of coupler U,nQnD"!t&  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) `O}bPwa{>  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. )"y]_}  
    T =40;                        % length of time:T*T0. B4;P)\ 2  
    dt = T/N;                     % time step 2pAshw1G  
    n = [-N/2:1:N/2-1]';          % Index L&~>(/*7U  
    t = n.*dt;   ]\:l><  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. )jN fQ!?/  
    w=2*pi*n./T; x:IY6  l  
    g1=-i*ww./2; ZQrgYeQl"  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; ?a-}1A{  
    g3=-i*ww./2; +4Lj}8,  
    P1=0; zy[|4Q(?  
    P2=0; s&qr2'F+z  
    P3=1; ,5Tw5<S  
    P=0; }ilX 2s?>  
    for m1=1:M1                 r#K"d  
    p=0.032*m1;                %input amplitude .s<tQU  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 , MU9p*  
    s1=s10; SQx:`{O  
    s20=0.*s10;                %input in waveguide 2 BGVy \F<  
    s30=0.*s10;                %input in waveguide 3 9i#K{CkC|  
    s2=s20; ]lzOz<0q  
    s3=s30; .A Z+|?d  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   XY`2>7  
    %energy in waveguide 1 (Zu V5|N  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   WjMP]ND#c  
    %energy in waveguide 2 =6+j Po{F  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   w'Q2Czso  
    %energy in waveguide 3 ;V3d"@R,  
    for m3 = 1:1:M3                                    % Start space evolution +)K yG  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS We*c_;@<  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; ?GKm_b]JC  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; ph=[|P)  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform yj{:%Km:`  
       sca2 = fftshift(fft(s2)); 5Ai$1'*p  
       sca3 = fftshift(fft(s3)); <0I=XsE1iX  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   j\8'P9~%  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); tc<t%]c  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); _ a,XL<9I  
       s3 = ifft(fftshift(sc3)); YJ^TO\4WM  
       s2 = ifft(fftshift(sc2));                       % Return to physical space dbLxm!;(  
       s1 = ifft(fftshift(sc1)); S~DY1e54GF  
    end ~j2=hkS  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); n;Etn!4M  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); )hai?v~g  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); -d6*M*{|  
       P1=[P1 p1/p10]; bwAL:  
       P2=[P2 p2/p10]; Bh,LJawE  
       P3=[P3 p3/p10]; 0,`$KbV\  
       P=[P p*p]; I3V>VLv  
    end i<Be)Y-'  
    figure(1) /1q] D8  
    plot(P,P1, P,P2, P,P3); }ZWeb#\  
    <=,KP)   
    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~!~