切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9185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 !`Le`c  
    P> |Ef~j  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of Sq<3Rw  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of _'&k#Q  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear 0Qt~K#mr/  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 y`({ .L  
    TWtC-wI;  
    %fid=fopen('e21.dat','w'); D_Guc8*  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) #o~[1K+Yq  
    M1 =3000;              % Total number of space steps h:_NA  
    J =100;                % Steps between output of space Mg+4huT  
    T =10;                  % length of time windows:T*T0 u9BjgK(M  
    T0=0.1;                 % input pulse width ;>5,  
    MN1=0;                 % initial value for the space output location lelMt=  
    dt = T/N;                      % time step c+H)ed>  
    n = [-N/2:1:N/2-1]';           % Index 1}`2\3,  
    t = n.*dt;   ssPI$IRg!  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 H)\4=^  
    u20=u10.*0.0;                  % input to waveguide 2 s88y{o  
    u1=u10; u2=u20;                 s_TD4~ $  
    U1 = u1;   NfOp=X?Y  
    U2 = u2;                       % Compute initial condition; save it in U )]3L/  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. ve6x/ PD  
    w=2*pi*n./T; E3bwyK!s  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T ]uAS+shQ&  
    L=4;                           % length of evoluation to compare with S. Trillo's paper <;aJ#qT  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 )}q uw"H  
    for m1 = 1:1:M1                                    % Start space evolution #sS9vv7i  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS 6vF/e#},  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; v O PMgEI  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform n?}5!  
       ca2 = fftshift(fft(u2)); eJW[ ]!  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation *l:&f_ngV  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   Fk aXA.JE  
       u2 = ifft(fftshift(c2));                        % Return to physical space UP?D@ogl<  
       u1 = ifft(fftshift(c1)); tR5tPPw  
    if rem(m1,J) == 0                                 % Save output every J steps. 6A.P6DW  
        U1 = [U1 u1];                                  % put solutions in U array >r=6A   
        U2=[U2 u2];  J+lGh9G  
        MN1=[MN1 m1]; z$66\/V']  
        z1=dz*MN1';                                    % output location T30Zk*V  
      end ^g[J*{+!W  
    end svqvG7  
    hg=abs(U1').*abs(U1');                             % for data write to excel Nkx0CG*  
    ha=[z1 hg];                                        % for data write to excel i0iez9B  
    t1=[0 t']; I.-v?1>,  
    hh=[t1' ha'];                                      % for data write to excel file v[smQO  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format Ajg\aof0{  
    figure(1) <$Ztik1  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn (2d3jQN`  
    figure(2) 1g~y]iQ  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn #>XeR>T  
    <>n9'i1  
    非线性超快脉冲耦合的数值方法的Matlab程序 <&6u]uKrW  
    viJJ e'\2  
    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。   BW>5?0E[4(  
    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 9{$8\E9*nd  
    Hg aZbb>'  
    /,LfA2^_j{  
    ;$z7[+M  
    %  This Matlab script file solves the nonlinear Schrodinger equations l0:5q?g  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of x^X$M$o,l  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear Hsgy'X%om  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 3(C :X1  
    (![t_r0  
    C=1;                           bs BZ E  
    M1=120,                       % integer for amplitude bQ"N ;d)e  
    M3=5000;                      % integer for length of coupler K?[)E3  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) 6{8/P'@/Zz  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. -p]>Be+^x  
    T =40;                        % length of time:T*T0. %<AS?Ry  
    dt = T/N;                     % time step hF.6}28U1  
    n = [-N/2:1:N/2-1]';          % Index r ^ Y~mq  
    t = n.*dt;   $o"g73`3  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. JtFiFaCxY  
    w=2*pi*n./T; nP OO3!<{  
    g1=-i*ww./2; +aj^Cs1$  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; rFfy#e  
    g3=-i*ww./2; 0E1=W 6UZ  
    P1=0; Z}+yI,  
    P2=0; [Y$V\h=V  
    P3=1; Z(`r-}f I  
    P=0; @/ k x er  
    for m1=1:M1                 f1J %]g!  
    p=0.032*m1;                %input amplitude _Z.cMYN  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 ;iQp7aW{$  
    s1=s10; GG+5/hU  
    s20=0.*s10;                %input in waveguide 2 Z\'wm'  
    s30=0.*s10;                %input in waveguide 3 {>h97}P  
    s2=s20; }PZ=`w*O  
    s3=s30; 'W(xgOP1  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   !UcOl0"6  
    %energy in waveguide 1 Hd374U<8]T  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   rREzM)GA  
    %energy in waveguide 2 <sc\EK  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   nP;;MX:B  
    %energy in waveguide 3 -X8eabb  
    for m3 = 1:1:M3                                    % Start space evolution LipxAE?O  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS s1=+::  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; `kPc!I7Y  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; \K}aQKB/j  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform SOj`Y|6^:  
       sca2 = fftshift(fft(s2)); Wcn[gn<  
       sca3 = fftshift(fft(s3)); 3S;N(A4  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   :".w{0l@  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); +Vy_9I(4Z  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); :XYy7xz<  
       s3 = ifft(fftshift(sc3)); 1eD.:_t4  
       s2 = ifft(fftshift(sc2));                       % Return to physical space /PW&$P1.]"  
       s1 = ifft(fftshift(sc1)); S=PJhAF  
    end 6c &Y  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); :Eo8v$W\RB  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); V7@ { D  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); R04J3D|  
       P1=[P1 p1/p10]; /WYh[XKe  
       P2=[P2 p2/p10]; Q;wB{vr$  
       P3=[P3 p3/p10]; !+KhFC&Py  
       P=[P p*p]; f'_M0x  
    end anC+r(jjg9  
    figure(1) Dft%ip2  
    plot(P,P1, P,P2, P,P3); ;RHNRVP  
    !.-.#<<_a  
    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~!~