切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 8939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 YF>t{|  
    N`Bt|#R  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of UWn}0:6t  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of v[a#>!;s  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear ;mi0Q.  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 Xq>e]#gR  
    z}bnw2d]  
    %fid=fopen('e21.dat','w'); z{#F9'\&  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) >>$IHz4Z"  
    M1 =3000;              % Total number of space steps b=|&0B$E  
    J =100;                % Steps between output of space :LBe{Jbw  
    T =10;                  % length of time windows:T*T0 cZ!s/^o?f  
    T0=0.1;                 % input pulse width 0dcXgP  
    MN1=0;                 % initial value for the space output location kmc9P&  
    dt = T/N;                      % time step o~-X7)]  
    n = [-N/2:1:N/2-1]';           % Index TLSy+x_gX  
    t = n.*dt;   ;2@sn+@  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 @i{JqHU"  
    u20=u10.*0.0;                  % input to waveguide 2 9)l_(*F  
    u1=u10; u2=u20;                 .@6]_h;  
    U1 = u1;   MW`a>'0t?  
    U2 = u2;                       % Compute initial condition; save it in U |Lhz^5/  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. ]R4)FH|><  
    w=2*pi*n./T; Yip9K[  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T amBz75N{  
    L=4;                           % length of evoluation to compare with S. Trillo's paper #h3+T*5} 6  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 3-mw-;.  
    for m1 = 1:1:M1                                    % Start space evolution phc1AN=[E  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS l#~Fe D  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; 44W3U~1  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform %C3cdy_c  
       ca2 = fftshift(fft(u2)); *}_/:\v  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation y2+a2  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   :>X7(&j8  
       u2 = ifft(fftshift(c2));                        % Return to physical space h+74W0 $  
       u1 = ifft(fftshift(c1)); 4iLU "~  
    if rem(m1,J) == 0                                 % Save output every J steps. MtYP3:  
        U1 = [U1 u1];                                  % put solutions in U array *b)b#p  
        U2=[U2 u2]; q~^:S~q  
        MN1=[MN1 m1]; %UQ{'JW?K  
        z1=dz*MN1';                                    % output location uWWv`bI>x  
      end (t]>=p%4g  
    end .u*].As=  
    hg=abs(U1').*abs(U1');                             % for data write to excel zl:D|h77  
    ha=[z1 hg];                                        % for data write to excel $1?X%8V  
    t1=[0 t']; <=inogf  
    hh=[t1' ha'];                                      % for data write to excel file o(``7A@7a  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format @}?D<O8#"#  
    figure(1) V^{!d}  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn {6n \532@  
    figure(2) `e9uSF:9C  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn bvgD;:Aj  
    .]e6TFsrO  
    非线性超快脉冲耦合的数值方法的Matlab程序 w3w*"M  
    vf yv a  
    在研究脉冲在非线性耦合器中的演变时,我们需要求解非线性偏微分方程组。在如下的论文中,我们提出了一种简洁的数值方法。 这里我们提供给大家用Matlab编写的计算程序。   A pjqSz"  
    Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 0l6iv[qu5w  
    SNU bY6  
    cP2R2 4th  
    yy } 0_  
    %  This Matlab script file solves the nonlinear Schrodinger equations o3yqG#dA  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of `_'Dj>  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear d8kwW!m+  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 ]= NYvv>H  
    c_q+_$t  
    C=1;                           IA^)`l7H  
    M1=120,                       % integer for amplitude .O#lab`:2  
    M3=5000;                      % integer for length of coupler z{g<y^Im+E  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) ]R{"=H'  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. ,&?q}M  
    T =40;                        % length of time:T*T0. W`'|&7~  
    dt = T/N;                     % time step iy82QNe  
    n = [-N/2:1:N/2-1]';          % Index mG~y8nUtp  
    t = n.*dt;   XC1lo4|  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. .:ZXtU  
    w=2*pi*n./T; arLl8G[  
    g1=-i*ww./2; 8~ )[d!'  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; y+scJ+<  
    g3=-i*ww./2; IJc#)J.2A  
    P1=0; s~$4bN>LD  
    P2=0; j$|C/E5?  
    P3=1; 0o|,& K  
    P=0; )Zf}V0!?+  
    for m1=1:M1                 B ^(rUR  
    p=0.032*m1;                %input amplitude Kg`x9._2  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 IVzA>Vd  
    s1=s10; jN} 7Bb X  
    s20=0.*s10;                %input in waveguide 2 87(^P3;@  
    s30=0.*s10;                %input in waveguide 3 HCIF9{o1j>  
    s2=s20; -fx88  
    s3=s30; ]XG n2U\  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   4D8yb|o  
    %energy in waveguide 1 DsW`V~ T  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   PBs<8xBx^  
    %energy in waveguide 2 c;rp@_ULG?  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   *@arn Eu  
    %energy in waveguide 3 `VFl|o#H  
    for m3 = 1:1:M3                                    % Start space evolution f5GR#3-h(  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS z{3%Hq  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; <Ihed |  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; ]az} n(B,  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform kw^Dp[8X  
       sca2 = fftshift(fft(s2)); /-YlC (kL  
       sca3 = fftshift(fft(s3)); <oaBh)=7  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   N"x\YHp  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); ) .-(-6=R  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); TnBGMI,g'  
       s3 = ifft(fftshift(sc3)); FV6he [,  
       s2 = ifft(fftshift(sc2));                       % Return to physical space cevV<Wy+  
       s1 = ifft(fftshift(sc1)); @ U8}sH^  
    end eN<pU%7  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); VtzmY  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); 30(m-D$K>9  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); 1xdESorX(  
       P1=[P1 p1/p10]; ~R?dDL  
       P2=[P2 p2/p10]; <,X+`m&  
       P3=[P3 p3/p10]; v*'iWHCl,  
       P=[P p*p]; Ul713Bjz  
    end ~2A$R'xb  
    figure(1) 8@W/43K8-  
    plot(P,P1, P,P2, P,P3); FP'u)eU&3  
    3@F+E\k  
    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~!~