切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9168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 - I~\  
    JE;!~=   
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of Qn@[{%),4  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of ~;oaW<"  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear +,eF(VS!  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 O/oLQoH  
    r$,Xv+}  
    %fid=fopen('e21.dat','w'); Pe@*')o*  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) ^,Ft7JAn  
    M1 =3000;              % Total number of space steps &InFC5A  
    J =100;                % Steps between output of space H$6;{IUz~  
    T =10;                  % length of time windows:T*T0 D#d/?\2  
    T0=0.1;                 % input pulse width E/^N   
    MN1=0;                 % initial value for the space output location ,oJ$m$(Lj  
    dt = T/N;                      % time step !" @<!  
    n = [-N/2:1:N/2-1]';           % Index *tl;0<n  
    t = n.*dt;   {7EpljH@  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 Wyb+K)Tg  
    u20=u10.*0.0;                  % input to waveguide 2 D+Z2y1  
    u1=u10; u2=u20;                 @$;I%  
    U1 = u1;   .Z@iz5  
    U2 = u2;                       % Compute initial condition; save it in U #eKH'fE  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. |[$ TT$Fb  
    w=2*pi*n./T; R^yh,  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T ZU l-&P_X  
    L=4;                           % length of evoluation to compare with S. Trillo's paper n -xCaq  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 L!Gpk)}[i  
    for m1 = 1:1:M1                                    % Start space evolution <4-g2.\  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS `F_R J.g*p  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; 5GURfG3{  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform ~b6c:db3  
       ca2 = fftshift(fft(u2)); WA#y&  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation w$jSlgUHy)  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   q( %)^C  
       u2 = ifft(fftshift(c2));                        % Return to physical space 4UMOC_  
       u1 = ifft(fftshift(c1)); $Q=S`z=  
    if rem(m1,J) == 0                                 % Save output every J steps. Y,-! QFS#  
        U1 = [U1 u1];                                  % put solutions in U array Xj<xen(  
        U2=[U2 u2]; <ti,Wn.  
        MN1=[MN1 m1];  4Gj  
        z1=dz*MN1';                                    % output location :,.HJ[Vg&  
      end FMT_X  
    end yL23 Nqe  
    hg=abs(U1').*abs(U1');                             % for data write to excel Ys<z%  
    ha=[z1 hg];                                        % for data write to excel X#ud_+6x  
    t1=[0 t']; D@m3bsMwe  
    hh=[t1' ha'];                                      % for data write to excel file UTO$L|K  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format UW{C`^?=B  
    figure(1) 5 axt\  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn }wC=p>zA  
    figure(2) ~NIqO4 D  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn af&P;#U  
    D&D-E~b^  
    非线性超快脉冲耦合的数值方法的Matlab程序 }5}#QHF  
    U[hokwZ  
    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。   gj4ONmY  
    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 PVrNS7 Rk/  
     X*`b}^T  
    4XSq\.@G  
    !y3XIbdS"  
    %  This Matlab script file solves the nonlinear Schrodinger equations %U9f`qE  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of k>:\4uI|<\  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear %Ybr5$_  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 27Vx<W  
    zG<>-?q~'  
    C=1;                           m[hHaX  
    M1=120,                       % integer for amplitude ,8stEp9~h]  
    M3=5000;                      % integer for length of coupler Wli!s~c5Fo  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) SfPtG  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. '_" S/X +v  
    T =40;                        % length of time:T*T0. .G>~xm0  
    dt = T/N;                     % time step GYV%RD#  
    n = [-N/2:1:N/2-1]';          % Index xiF}{25a  
    t = n.*dt;   xo{z4W  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. G~/*!?&z  
    w=2*pi*n./T; [>lQi X  
    g1=-i*ww./2; d,o|>e$  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; jV#1d8qm  
    g3=-i*ww./2;  }S}%4c>  
    P1=0; ?_. SV g  
    P2=0; M[L@ej  
    P3=1; 0SJ(Ln`0K  
    P=0; j+2-Xy'  
    for m1=1:M1                 2c3/iYCKP  
    p=0.032*m1;                %input amplitude wIF)(t-):  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 n.1$p  
    s1=s10; Iv?1XI=  
    s20=0.*s10;                %input in waveguide 2 hPt=j{aJ%<  
    s30=0.*s10;                %input in waveguide 3 w} r mYQ  
    s2=s20; 7Kt i&T  
    s3=s30; LftzW{>gI"  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   ~$YasFEz  
    %energy in waveguide 1 9 $zx<O  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   Rj-4K@a8#N  
    %energy in waveguide 2 y4Nam87;/?  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   Ee=!bv(%70  
    %energy in waveguide 3 H:o=gP60]  
    for m3 = 1:1:M3                                    % Start space evolution \mw5 ~Rf;  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS 1(jx.W3  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; `-5gsJ  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; ~jJe|zg>  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform KD'}9{F,  
       sca2 = fftshift(fft(s2)); 3H%bbFy  
       sca3 = fftshift(fft(s3)); 6`5DR~  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   ;s5JYR  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); f_IsY+@  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); h-\+# .YP  
       s3 = ifft(fftshift(sc3)); Q>uJ:[x+  
       s2 = ifft(fftshift(sc2));                       % Return to physical space ge% tj O  
       s1 = ifft(fftshift(sc1)); #YSFiy:+r_  
    end S*H @`Do%d  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); x'V:qv*O  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); E-#C#B  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); ty8E;[ '  
       P1=[P1 p1/p10]; J$,bsMIX  
       P2=[P2 p2/p10]; 8>(/:u_x  
       P3=[P3 p3/p10]; &Vg)/t;  
       P=[P p*p]; "f-HOd\=  
    end 5B;;{GR  
    figure(1) VRUA<x  
    plot(P,P1, P,P2, P,P3); V|pO";%>,  
    aQ0pYk~(  
    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~!~