切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 8956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 S mjg[  
    \UR/tlw+/  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of _6/q.  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of j+-+<h/(  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear H6! <y-  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 C?h`i ^ >2  
    "JBTsQDj!  
    %fid=fopen('e21.dat','w'); P3u,)P&  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) 1}>uY  
    M1 =3000;              % Total number of space steps I6B4S"Q5<  
    J =100;                % Steps between output of space " +n\0j;  
    T =10;                  % length of time windows:T*T0 !5escR!\D  
    T0=0.1;                 % input pulse width *]]C.t-cd  
    MN1=0;                 % initial value for the space output location /N?vVp  
    dt = T/N;                      % time step q(YFt*(;w  
    n = [-N/2:1:N/2-1]';           % Index I,0Z* rw  
    t = n.*dt;   yD n8{uI  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 I nCo[ 8SI  
    u20=u10.*0.0;                  % input to waveguide 2 QZ:xG:qyk;  
    u1=u10; u2=u20;                 m=.}}DcSs  
    U1 = u1;   n>-"\cjV  
    U2 = u2;                       % Compute initial condition; save it in U !v`C-1}70  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. Wgr`)D  
    w=2*pi*n./T; Mq [|w2.  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T 2B<0|EGtzw  
    L=4;                           % length of evoluation to compare with S. Trillo's paper 3Hg}G#]WS  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 Bx&F*a;5  
    for m1 = 1:1:M1                                    % Start space evolution ``j8T[g  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS 7\e96+j|f  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; g\O&gNq<)-  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform ^>H+#@R  
       ca2 = fftshift(fft(u2)); LG6k KG  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation e_{!8u.+  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   28rC>*+z  
       u2 = ifft(fftshift(c2));                        % Return to physical space H*&ZX AKv  
       u1 = ifft(fftshift(c1)); ?5yj</W  
    if rem(m1,J) == 0                                 % Save output every J steps. ! !9l@  
        U1 = [U1 u1];                                  % put solutions in U array SSh=r  
        U2=[U2 u2]; W<"{d  
        MN1=[MN1 m1]; rt5eN:'qY  
        z1=dz*MN1';                                    % output location i9FtS7  
      end b}OOG  
    end C1 YG=!  
    hg=abs(U1').*abs(U1');                             % for data write to excel _s> ZY0  
    ha=[z1 hg];                                        % for data write to excel [q5N 4&q\  
    t1=[0 t']; :a#p zEK  
    hh=[t1' ha'];                                      % for data write to excel file 1G6MO  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format >tFv&1iR  
    figure(1) ^& R H]q  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn ^twJNm{99  
    figure(2) z%pD3J?>  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn nR()ei^X  
    D#?jddr-  
    非线性超快脉冲耦合的数值方法的Matlab程序 /j0zb&  
    /V% ]lmxQ  
    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。   djxM/"xo  
    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 J/o$\8tiMw  
    D" 4*&  
    (3;dtp>Xx  
    ^ew<|J2,B  
    %  This Matlab script file solves the nonlinear Schrodinger equations S ;; Z  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of '\iWp?`$  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear $)fybn Y  
    %  pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 U.[?1:v  
    \f AL:mJ  
    C=1;                           1>!wm0;x  
    M1=120,                       % integer for amplitude s, 8a1o  
    M3=5000;                      % integer for length of coupler jD eNCJ  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) RXj6L~vs5_  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. 3hrODts  
    T =40;                        % length of time:T*T0. `S{Blv  
    dt = T/N;                     % time step =CE(M},d  
    n = [-N/2:1:N/2-1]';          % Index E9yBa=#*c  
    t = n.*dt;   v FL\O  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. i{$h]D_fD  
    w=2*pi*n./T; Po: )b  
    g1=-i*ww./2; # XD-a  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; bxS+ R\  
    g3=-i*ww./2; 3N ]  
    P1=0; /W6r{Et  
    P2=0; 71h?t`N  
    P3=1; u*<G20~A  
    P=0; 0H6^2T<  
    for m1=1:M1                 ~ }<!ON;  
    p=0.032*m1;                %input amplitude h]#wwJF  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 +foyPj!%  
    s1=s10; r.V< 5xV  
    s20=0.*s10;                %input in waveguide 2 =7Wr  
    s30=0.*s10;                %input in waveguide 3 C98 Ks  
    s2=s20; 7D;g\{>M  
    s3=s30; +6xEz67A<  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   Pkm3&sW  
    %energy in waveguide 1 ~x>?1K  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   #h 4`f  
    %energy in waveguide 2 ]/p)XHKo  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   'e3[m  
    %energy in waveguide 3 |^ao,3h#  
    for m3 = 1:1:M3                                    % Start space evolution oM@X)6P_  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS |Q'l&Gt6  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; zLs[vg.(  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; H@uCbT  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform {ER%r'(4Z  
       sca2 = fftshift(fft(s2)); 8qEK6-  
       sca3 = fftshift(fft(s3)); @CSTp6{y  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   COx<X\  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); kW#{[,7r  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); #l(cBM9sz  
       s3 = ifft(fftshift(sc3)); (L)tC*Qjc  
       s2 = ifft(fftshift(sc2));                       % Return to physical space @+v;B:  
       s1 = ifft(fftshift(sc1)); P| [i{h  
    end 2[\I{<2/9  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); EcA@bZ0  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); 9M)N2+hkZ  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); ,Z7tpFC  
       P1=[P1 p1/p10]; i6^COr  
       P2=[P2 p2/p10]; dz',!|>  
       P3=[P3 p3/p10]; %C]K`=vI-  
       P=[P p*p]; 2/9P&c-rp  
    end }Om+,!_d  
    figure(1) Z7eD+4gD  
    plot(P,P1, P,P2, P,P3); !cs +tm3  
    s^nwF>  
    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~!~