切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 9155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 m3bCZ 9iE  
    !-<p,z  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of |`TgX@,#9  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of 1)m@?CaI`  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear }e2VY  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 Ep9W-n?}  
    zcrY>t#l  
    %fid=fopen('e21.dat','w'); ":a\z(*t  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) 3cdTed-MIh  
    M1 =3000;              % Total number of space steps d?wc*N3  
    J =100;                % Steps between output of space +M' H0-[  
    T =10;                  % length of time windows:T*T0 JN+_|`  
    T0=0.1;                 % input pulse width &i+Ce  
    MN1=0;                 % initial value for the space output location B"yFS7Rrj  
    dt = T/N;                      % time step =X\^J  
    n = [-N/2:1:N/2-1]';           % Index ,R%q}IH#  
    t = n.*dt;   [e[<p\]  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 BTgG4F/)  
    u20=u10.*0.0;                  % input to waveguide 2 I[)%,jd  
    u1=u10; u2=u20;                 Wbr+ KX8)  
    U1 = u1;   7f rTTSZ  
    U2 = u2;                       % Compute initial condition; save it in U f+8wl!M+6  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. .*m>\>Gsgw  
    w=2*pi*n./T; *na?n2Yzt  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T <sK4#!K  
    L=4;                           % length of evoluation to compare with S. Trillo's paper q9Y9w(  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 [ ol9|sdu  
    for m1 = 1:1:M1                                    % Start space evolution `x%'jPP1 ^  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS Z}$TKO*u  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; BauU{:Sh  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform F*"}aP$  
       ca2 = fftshift(fft(u2)); okbQ<{9  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation 7}M2bH} \K  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   /|* Y2ETOr  
       u2 = ifft(fftshift(c2));                        % Return to physical space 93Co}@Y;Y+  
       u1 = ifft(fftshift(c1)); '>r7V  
    if rem(m1,J) == 0                                 % Save output every J steps. i3rH'B -I.  
        U1 = [U1 u1];                                  % put solutions in U array Fu!RhsW5j  
        U2=[U2 u2]; 'yMF~r3J  
        MN1=[MN1 m1]; &=VDASEu  
        z1=dz*MN1';                                    % output location ^0/j0]O  
      end nBk)WX&[K  
    end (sh)TBb5  
    hg=abs(U1').*abs(U1');                             % for data write to excel 0PlO(" ,a  
    ha=[z1 hg];                                        % for data write to excel v`M3eh@$A  
    t1=[0 t']; z`:lcF{V  
    hh=[t1' ha'];                                      % for data write to excel file RzWXKBI\E]  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format Y "/]|'p  
    figure(1) o!)3?  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn [VE8V-  
    figure(2) +E{|63~q  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn yu;P +G  
    iof-7{+3_  
    非线性超快脉冲耦合的数值方法的Matlab程序 6I%5Q4Ll  
    iyg*Xbmi~.  
    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。   O#F4WWF  
    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 EOCN&_Z;  
    [eC2"&}  
    tCdqh-   
    V,%=AR5  
    %  This Matlab script file solves the nonlinear Schrodinger equations ,^C--tgZJg  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of H '  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear DQ r Y*nH  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 0tXS3+@n =  
    ;C2K~8,  
    C=1;                           NuQdSj_>  
    M1=120,                       % integer for amplitude >Wv;R2|  
    M3=5000;                      % integer for length of coupler T\D}kQM  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) "vOwd.(?N  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. ,%M$0poKM  
    T =40;                        % length of time:T*T0. tNbN7yI  
    dt = T/N;                     % time step v_DedVhe  
    n = [-N/2:1:N/2-1]';          % Index / G7vwC  
    t = n.*dt;   s+<Yg$)  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. 8|\8O@  
    w=2*pi*n./T; Sy0$z39  
    g1=-i*ww./2; a ?)NC  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; 0 eDHu  
    g3=-i*ww./2; Zcx`SC-0  
    P1=0; =,6z4" )  
    P2=0; Zg{KFM%  
    P3=1; tM'P m   
    P=0; 1pgU}sRk  
    for m1=1:M1                 <nT +$  
    p=0.032*m1;                %input amplitude }khV'6"'|  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 v@ lM3_rbO  
    s1=s10; {+Rog/;S'  
    s20=0.*s10;                %input in waveguide 2 |l]XpWV  
    s30=0.*s10;                %input in waveguide 3 ^f4s"T  
    s2=s20; k@k&}N0{  
    s3=s30; rE.;g^4p  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   8|l\E VV6  
    %energy in waveguide 1 paCV!tP  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   P*3BB>FO   
    %energy in waveguide 2 1cpiHZa  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   .uMn0PE   
    %energy in waveguide 3 n'E(y)9|  
    for m3 = 1:1:M3                                    % Start space evolution Bf~vA4  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS r{L> F]Tw  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; U@uGNMKR  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; 0dE@c./R i  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform S.-TOE  
       sca2 = fftshift(fft(s2)); C26>BU<  
       sca3 = fftshift(fft(s3)); -"' j7t:  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   w"-Lc4t+  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); ,9zjFI  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); 3q\,$*D.  
       s3 = ifft(fftshift(sc3)); 5K>3My#  
       s2 = ifft(fftshift(sc2));                       % Return to physical space iJ1"at  
       s1 = ifft(fftshift(sc1)); FQ<Ju.  
    end 4;yKOQD|  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); !Prg_6 `  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); &8Cu#^3  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); Q ayPo]O  
       P1=[P1 p1/p10]; 3Q.#c,`jV  
       P2=[P2 p2/p10]; 7&jTtKLj  
       P3=[P3 p3/p10]; n|9-KTe7|*  
       P=[P p*p]; 5YE'L.  
    end -#u=\8  
    figure(1) r1 !@hT  
    plot(P,P1, P,P2, P,P3); Hq:X{)"  
    I9_RlAd  
    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~!~