切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9453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 gHc0n0ZV  
    FaO=<jYi  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of D/pc)3Ofe  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of 8d.5D&  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear Wi]Mp7b  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 $8#zPJR&  
    zTb!$8D"g  
    %fid=fopen('e21.dat','w'); gd3~R+Kd  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) S;[g0j  
    M1 =3000;              % Total number of space steps F/;uN5{o  
    J =100;                % Steps between output of space {2?o:  
    T =10;                  % length of time windows:T*T0 _:F0>=$  
    T0=0.1;                 % input pulse width afY~Y?PJ<  
    MN1=0;                 % initial value for the space output location .zf#S0y%(  
    dt = T/N;                      % time step g}nlb.b]{m  
    n = [-N/2:1:N/2-1]';           % Index j]i:~9xKW  
    t = n.*dt;   }Jkz0JY~  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 _hlLM,p  
    u20=u10.*0.0;                  % input to waveguide 2 o#Q0J17i?  
    u1=u10; u2=u20;                 L2:v#c()#)  
    U1 = u1;   3n-~+2l  
    U2 = u2;                       % Compute initial condition; save it in U tM3eB= .*  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. N3 qtq9{  
    w=2*pi*n./T; dbF?#s~u  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T P}B{FIpNG  
    L=4;                           % length of evoluation to compare with S. Trillo's paper ??Zh$^No:  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 +$R4'{9q  
    for m1 = 1:1:M1                                    % Start space evolution 6rlafISvO  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS p%A s6.  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; B;.]<k'3  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform W9>q1  
       ca2 = fftshift(fft(u2)); wRu+:<o^.  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation QV/ o;  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   B ^>}M  
       u2 = ifft(fftshift(c2));                        % Return to physical space QfjgBJo%  
       u1 = ifft(fftshift(c1));  )! 2$yD  
    if rem(m1,J) == 0                                 % Save output every J steps. Z%_"-ENT  
        U1 = [U1 u1];                                  % put solutions in U array r}ZL{uWMW  
        U2=[U2 u2]; !#P|2>>u  
        MN1=[MN1 m1]; PScq-*^  
        z1=dz*MN1';                                    % output location \d~sU,L;]  
      end kGbtZ} W  
    end kc#<Gr&Z&  
    hg=abs(U1').*abs(U1');                             % for data write to excel Yg_;Eu0'?  
    ha=[z1 hg];                                        % for data write to excel wWV`k  
    t1=[0 t']; QRb iO  
    hh=[t1' ha'];                                      % for data write to excel file c\.Hs9T >  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format *3 .+19Q  
    figure(1) =ZdP0l+V=k  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn \ci'Cbn\o  
    figure(2) D{1k{/cF  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn D=*3Xd  
    Y] Q=kI  
    非线性超快脉冲耦合的数值方法的Matlab程序 {=n-S2%  
    m]t`;lr<  
    在研究脉冲在非线性耦合器中的演变时,我们需要求解非线性偏微分方程组。在如下的论文中,我们提出了一种简洁的数值方法。 这里我们提供给大家用Matlab编写的计算程序。   UzZzt$Kw  
    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 bs{i@1$  
    ];cJIa  
    y" 4Nw]kU  
    CMk0(sztU_  
    %  This Matlab script file solves the nonlinear Schrodinger equations Th&-n%r9K  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of .{,PC  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear Bn>"lDf,  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 Lo"w,p`n@  
    0< i]ph  
    C=1;                           $#q:\yQsPC  
    M1=120,                       % integer for amplitude ,S.<qmf  
    M3=5000;                      % integer for length of coupler @lvvI<U  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) $Pw@EC]  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. 9C;Hm>WEpP  
    T =40;                        % length of time:T*T0. x3cno#  
    dt = T/N;                     % time step s^:8bFn9$  
    n = [-N/2:1:N/2-1]';          % Index dg#w/}}m  
    t = n.*dt;   !brXQj8D7  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. P,.<3W"4i  
    w=2*pi*n./T; >^mNIfdE^=  
    g1=-i*ww./2; t;?M#I\,{  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; <_X`D4g]XO  
    g3=-i*ww./2; ySC;;k'  
    P1=0; d4'*K1m   
    P2=0; 34k}7k~n  
    P3=1; xqV>m  
    P=0; uCX+Lw+As  
    for m1=1:M1                 \^=Wp'5R  
    p=0.032*m1;                %input amplitude =*K~U# uoC  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 j SLC L'  
    s1=s10; "M e)'  
    s20=0.*s10;                %input in waveguide 2 []opPQ 1  
    s30=0.*s10;                %input in waveguide 3 C)w11$.YQ9  
    s2=s20; O3H~|R+^  
    s3=s30; cE}y~2cH  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   Mlr]-Gu5Z  
    %energy in waveguide 1 @y3u'Y,B  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   :-Gf GL>]  
    %energy in waveguide 2 QL_~E;U  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   y^utMH  
    %energy in waveguide 3 ssdpwn'  
    for m3 = 1:1:M3                                    % Start space evolution )C \ %R  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS R4xoc;b  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; \?n4d#=$o  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; 2L=+z1%I  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform 4}mp~AXy;z  
       sca2 = fftshift(fft(s2)); 9wR-0E )  
       sca3 = fftshift(fft(s3)); 3_%lN4sz  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   U%E6"Hg  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); 8&q|*/2  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); (wxdT6RVm\  
       s3 = ifft(fftshift(sc3)); j,7NLb9M  
       s2 = ifft(fftshift(sc2));                       % Return to physical space ?`& l Y  
       s1 = ifft(fftshift(sc1)); {Pi+VuLE  
    end sY @S  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); jlhyn0  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); CYIp 3D'k  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); eh`sfH  
       P1=[P1 p1/p10]; z^tws*u],5  
       P2=[P2 p2/p10]; qs$%/  
       P3=[P3 p3/p10]; hqEn D  
       P=[P p*p]; l)JNNcej  
    end )(&Z&2~A  
    figure(1) /jBjqE;_  
    plot(P,P1, P,P2, P,P3); #Y)Gos  
    ym>>5(bni  
    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~!~