切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 8983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 j@u]( nf  
    @s.civ!Yk  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of G nPrwDB  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of 8yDe{  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear c4V%>A  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 yQ!I`T>a  
    s3sPj2e{  
    %fid=fopen('e21.dat','w'); E< Y!BT[X  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) `F`{s`E)  
    M1 =3000;              % Total number of space steps oH='\M%+  
    J =100;                % Steps between output of space |}><)}  
    T =10;                  % length of time windows:T*T0 r t0_[i  
    T0=0.1;                 % input pulse width  <BiSx  
    MN1=0;                 % initial value for the space output location ?>s[B7wMp  
    dt = T/N;                      % time step U!i1~)s  
    n = [-N/2:1:N/2-1]';           % Index WCD)yTg:ES  
    t = n.*dt;   e);`hNLih  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10  35%\"Y?  
    u20=u10.*0.0;                  % input to waveguide 2 K1$   
    u1=u10; u2=u20;                 +3F%soum95  
    U1 = u1;   $W]}m"l  
    U2 = u2;                       % Compute initial condition; save it in U Jo''yrJpB  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. RJ1 @ a  
    w=2*pi*n./T; Dv"HFQuF  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T 43?uTnX/  
    L=4;                           % length of evoluation to compare with S. Trillo's paper +L|x^ B3  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 46##(4RF  
    for m1 = 1:1:M1                                    % Start space evolution FrC)2wX  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS v>0I=ut  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; C2{*m{ D  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform oy-y Q YX  
       ca2 = fftshift(fft(u2)); MfZamu5+F  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation 0b G#'.-  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   C#LTF-$])  
       u2 = ifft(fftshift(c2));                        % Return to physical space '*B%&QC-  
       u1 = ifft(fftshift(c1)); OcLahz6  
    if rem(m1,J) == 0                                 % Save output every J steps. ;,/4Ry22j-  
        U1 = [U1 u1];                                  % put solutions in U array 5=#2@qp  
        U2=[U2 u2]; +rJDDIb  
        MN1=[MN1 m1]; " GY3sam  
        z1=dz*MN1';                                    % output location Ihp Ea,v)  
      end I0*N "07n  
    end B$M4f7  
    hg=abs(U1').*abs(U1');                             % for data write to excel E7q,6f3@r  
    ha=[z1 hg];                                        % for data write to excel *ze,X~8-  
    t1=[0 t']; y$+=>p|d.^  
    hh=[t1' ha'];                                      % for data write to excel file ,T*\9' Q  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format 6 2#@Y-5  
    figure(1) {53|X=D64  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn nC(Lr,(  
    figure(2) =~k}XB  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn ;nrkC\SYh:  
    Ma4eu8  
    非线性超快脉冲耦合的数值方法的Matlab程序 /dO*t4$@?  
    xR8y"CpE  
    在研究脉冲在非线性耦合器中的演变时,我们需要求解非线性偏微分方程组。在如下的论文中,我们提出了一种简洁的数值方法。 这里我们提供给大家用Matlab编写的计算程序。   {n&GZG"f  
    Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 x_t$*  
    >0_{80bdO  
     ~)F_FS  
    7K ~)7U  
    %  This Matlab script file solves the nonlinear Schrodinger equations zm8k,e +5-  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of {#~A `crO  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear V-3;7  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 AZf69z  
    YYL3a=;`a  
    C=1;                           A'$>~Ev  
    M1=120,                       % integer for amplitude <Sr:pm  
    M3=5000;                      % integer for length of coupler $4*gi&  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) Ii# +JY0k  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. - (7oFOtg  
    T =40;                        % length of time:T*T0. `n@;%*6/  
    dt = T/N;                     % time step * =*\w\ te  
    n = [-N/2:1:N/2-1]';          % Index gF`hlYD  
    t = n.*dt;   Vju/+  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. X"vDFE`?  
    w=2*pi*n./T; ~k%XW$cV  
    g1=-i*ww./2; VCVKh  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; !Na@T]J  
    g3=-i*ww./2; X,c`,B03  
    P1=0; r9*6=*J|  
    P2=0; 'y5H%I!  
    P3=1; >6Jz=N,  
    P=0; 7nB X@Uo  
    for m1=1:M1                 &bGf{P*Da  
    p=0.032*m1;                %input amplitude 'Fc$?$c\  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 p"7[heExw  
    s1=s10; P,b&F  
    s20=0.*s10;                %input in waveguide 2 !@*= b1  
    s30=0.*s10;                %input in waveguide 3 jcjl q-x  
    s2=s20; Q+/P>5O/  
    s3=s30; R T~oJ~t;  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   rxs:)# ?A  
    %energy in waveguide 1 R\Ckk;<$  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   9Fw NX  
    %energy in waveguide 2 #2lvRJB  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   8C? E1fH\  
    %energy in waveguide 3 OG_v[  C5  
    for m3 = 1:1:M3                                    % Start space evolution _k;HhLj`  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS )| |CU]"b?  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; J qmL|S)  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; .;S1HOHz4  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform yu@Pd3  
       sca2 = fftshift(fft(s2)); x <OVtAUB  
       sca3 = fftshift(fft(s3)); j/F('r~L  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   m>3\1`ZF~<  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); fW[RCd  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); =d iGuI B  
       s3 = ifft(fftshift(sc3)); }$sTnea  
       s2 = ifft(fftshift(sc2));                       % Return to physical space xJnN95`R@  
       s1 = ifft(fftshift(sc1)); NTO.;S|2%  
    end W`P>vK@=  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); MttFB;Tp  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); uRYq.`v,  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); 2[j`bYNe  
       P1=[P1 p1/p10]; Dd,i^,4Gj  
       P2=[P2 p2/p10]; t @a&&  
       P3=[P3 p3/p10]; /"8|26  
       P=[P p*p]; '1fyBU  
    end T\ukJ25!  
    figure(1) kBnb9'.A1  
    plot(P,P1, P,P2, P,P3); w~jm0jK]  
    LU8:]zOY  
    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~!~