切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9469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 <x->.R_  
    6i=Nk"d  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of  Z5[f  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of xA#'%|"  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear K[Ao_v2g  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 WEZ)>[Xj?  
    ;FH_qF`.  
    %fid=fopen('e21.dat','w'); .4cOMiG  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) B`;DAsmT  
    M1 =3000;              % Total number of space steps a"pejW`m  
    J =100;                % Steps between output of space bqI| wGCA"  
    T =10;                  % length of time windows:T*T0 4SGF8y@WU  
    T0=0.1;                 % input pulse width )u}MyFl.  
    MN1=0;                 % initial value for the space output location O~u@J'4  
    dt = T/N;                      % time step I/Q5Y-atg  
    n = [-N/2:1:N/2-1]';           % Index 1v"r8=Wt  
    t = n.*dt;   4K<T_B/  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 nd xijqw  
    u20=u10.*0.0;                  % input to waveguide 2 Q!(qL[o  
    u1=u10; u2=u20;                 w@Gk#  
    U1 = u1;   (U@uJ  
    U2 = u2;                       % Compute initial condition; save it in U *=~X1s  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. FK!UUy;  
    w=2*pi*n./T; DNp4U9  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T }rbsarG@  
    L=4;                           % length of evoluation to compare with S. Trillo's paper <Q%:c4N  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 fNZ:l=L3):  
    for m1 = 1:1:M1                                    % Start space evolution "YQ%j+  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS ,Y_[+  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; =^D{ZZw{  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform -mPrmapb3  
       ca2 = fftshift(fft(u2)); g$eZT{{W  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation u*C"d1v=  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   7J$5dFV2  
       u2 = ifft(fftshift(c2));                        % Return to physical space o7#Mr`6H  
       u1 = ifft(fftshift(c1)); |= U(8t  
    if rem(m1,J) == 0                                 % Save output every J steps. QnPgp(d <  
        U1 = [U1 u1];                                  % put solutions in U array @[] A&)B  
        U2=[U2 u2]; PdNxuy  
        MN1=[MN1 m1]; f8X/kz  
        z1=dz*MN1';                                    % output location eH y.<VX  
      end M!E#T-)  
    end /naGn@m5u  
    hg=abs(U1').*abs(U1');                             % for data write to excel W;9Jah.  
    ha=[z1 hg];                                        % for data write to excel 2xJT!lN  
    t1=[0 t']; Hz] p]  
    hh=[t1' ha'];                                      % for data write to excel file |Sf` Cs  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format A[.5Bi  
    figure(1) va_TC!{;  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn I-`qo7dQ_S  
    figure(2) -a(\(^NW  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn Y =BXV7\  
    *E-VS= #  
    非线性超快脉冲耦合的数值方法的Matlab程序 fpK`  
    +iL,8eW  
    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。   Hxm CKW!  
    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 $={WtR  
    raPUx_$PH  
    iTq~ ^9G  
    NXyuv7%5=  
    %  This Matlab script file solves the nonlinear Schrodinger equations I$7TnMug  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of l .wf= /  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear {=Ku9\  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 0Q_@2  
    <(%cb.^c=N  
    C=1;                           W%k0_Y/5  
    M1=120,                       % integer for amplitude m#oZu {  
    M3=5000;                      % integer for length of coupler 9ywPWT[^  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) ,UD,)ZPf[  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. i%R2#F7I  
    T =40;                        % length of time:T*T0. BkTGH.4G%  
    dt = T/N;                     % time step "[LSDE"(  
    n = [-N/2:1:N/2-1]';          % Index  8/|~E  
    t = n.*dt;   pdrF/U+  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. UkY `&&ic  
    w=2*pi*n./T; jSj (ZU6  
    g1=-i*ww./2; t/baze;V  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; %Jr6pmc  
    g3=-i*ww./2; ]GS@ub  
    P1=0; $K,6!FyBa  
    P2=0; FrNW@  
    P3=1; Kb#}f/  
    P=0; :K) =Hf2y  
    for m1=1:M1                 `[+nz rLkO  
    p=0.032*m1;                %input amplitude =lf&mD _/  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 w]{NaNIeq1  
    s1=s10; 7 vS]O$w<4  
    s20=0.*s10;                %input in waveguide 2 82X}@5o2  
    s30=0.*s10;                %input in waveguide 3 2Q,8@2w;  
    s2=s20; R":nG7o  
    s3=s30; wghz[qe  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   &!3=eVg  
    %energy in waveguide 1 ,cvLvN8  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   _faI*OY8  
    %energy in waveguide 2 $UZ4,S?V  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   I!)gXtJA"  
    %energy in waveguide 3 l_!.yV{  
    for m3 = 1:1:M3                                    % Start space evolution "}bk *2  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS up~l4]b+  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; z:aT5D  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; X^#.4:>.  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform )y7SkH|  
       sca2 = fftshift(fft(s2)); TXi$Q%0W  
       sca3 = fftshift(fft(s3)); C/Ig.KmXF{  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   27vLI~  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); ><X!~by  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); _[SP*" ]H  
       s3 = ifft(fftshift(sc3)); 1GY[1M1^  
       s2 = ifft(fftshift(sc2));                       % Return to physical space Musz+<]  
       s1 = ifft(fftshift(sc1)); d0b--v/  
    end }0#cdw#gH  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); vO1P%)  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); )>ed6A1  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); =*q:R9V  
       P1=[P1 p1/p10]; *|x2"?d-F:  
       P2=[P2 p2/p10]; Z;@F.r  
       P3=[P3 p3/p10]; 5hE8b  {V  
       P=[P p*p]; Y"mD)\Bw?  
    end a$MMp=p  
    figure(1) &50Kn[  
    plot(P,P1, P,P2, P,P3); C"/]X  
    j=)%~@  
    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~!~