切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 8949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 正序阅读 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 ?8$`GyjS  
    KK 7}q<&i  
    %  This Matlab script file solves the coupled nonlinear Schrodinger equations of 0m1V@ 3]7>  
    %  soliton in 2 cores coupler. The output pulse evolution plot is shown in Fig.1 of z(c8]Wu#  
    %  Youfa Wang and Wenfeng Wang, “A simple and effective numerical method for nonlinear lrc%GU):  
    %   pulse propagation in N-core optical couplers”, IEEE Photonics Technology lett. Vol.16, No.4, pp1077-1079, 2004 7Wef[N\x  
    &FmTT8"l  
    %fid=fopen('e21.dat','w'); wxB HlgK4z  
    N = 128;                       % Number of Fourier modes (Time domain sampling points) lO\HchG zB  
    M1 =3000;              % Total number of space steps PW@ :fM:q  
    J =100;                % Steps between output of space l'm|**  
    T =10;                  % length of time windows:T*T0 ,W+=N"`a'  
    T0=0.1;                 % input pulse width J8\l'} ?&  
    MN1=0;                 % initial value for the space output location U{dK8~  
    dt = T/N;                      % time step xpp nBnu$7  
    n = [-N/2:1:N/2-1]';           % Index Up%XBA  
    t = n.*dt;   Z?S?O#FED  
    u10=1.*sech(1*t);              % input to waveguide1 amplitude: power=u10*u10 Q^<amM!  
    u20=u10.*0.0;                  % input to waveguide 2 q/ :]+  
    u1=u10; u2=u20;                 d(}? \|  
    U1 = u1;   >]_6|Wfl  
    U2 = u2;                       % Compute initial condition; save it in U dlyGgaV*X  
    ww = 4*n.*n*pi*pi/T/T;         % Square of frequency. Note i^2=-1. }{+?>!qDt  
    w=2*pi*n./T; 7}qxWz  
    g=-i*ww./2;                    % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./T 3US`6Y"  
    L=4;                           % length of evoluation to compare with S. Trillo's paper v1i-O'  
    dz=L/M1;                       % space step, make sure nonlinear<0.05 n]vCvmt  
    for m1 = 1:1:M1                                    % Start space evolution A ___| #R  
       u1 = exp(dz*i*(abs(u1).*abs(u1))).*u1;          % 1st sSolve nonlinear part of NLS i9 CQ~  
       u2 = exp(dz*i*(abs(u2).*abs(u2))).*u2; ;fV"5H)U\  
       ca1 = fftshift(fft(u1));                        % Take Fourier transform -`ljKp  
       ca2 = fftshift(fft(u2)); "E7<S5 cr  
       c2=exp(g.*dz).*(ca2+i*1*ca1.*dz);               % approximation D|U bh]  
       c1=exp(g.*dz).*(ca1+i*1*ca2.*dz);               % frequency domain phase shift   kReZch}  
       u2 = ifft(fftshift(c2));                        % Return to physical space W`LG.`JW  
       u1 = ifft(fftshift(c1)); |{|B70v3Co  
    if rem(m1,J) == 0                                 % Save output every J steps. 512p\x@  
        U1 = [U1 u1];                                  % put solutions in U array gjD|f2*x  
        U2=[U2 u2]; fiC0'4.,  
        MN1=[MN1 m1]; 6|Dtx5 "r  
        z1=dz*MN1';                                    % output location LV9R ]  
      end ({Yfsf,  
    end A/9<} m  
    hg=abs(U1').*abs(U1');                             % for data write to excel Hwd^C 2v  
    ha=[z1 hg];                                        % for data write to excel Y\<w|LkD8  
    t1=[0 t']; `[E-V  
    hh=[t1' ha'];                                      % for data write to excel file 'N6oXE  
    %dlmwrite('aa',hh,'\t');                           % save data in the excel format z( ^?xv  
    figure(1) >~7XBb08  
    waterfall(t',z1',abs(U1').*abs(U1'))               % t' is 1xn, z' is 1xm, and U1' is mxn .>,Y |  
    figure(2) 5o{U$  
    waterfall(t',z1',abs(U2').*abs(U2'))               % t' is 1xn, z' is 1xm, and U1' is mxn ~Ih` ayVq  
    3,Z;J5VL4!  
    非线性超快脉冲耦合的数值方法的Matlab程序 o *U-.&  
    *eD[[HbKX  
    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。   r]}6iF.  
    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 \+Qd=,!i(  
    gCYe ^KJ  
    fb0)("_V  
    VWd`06'BN'  
    %  This Matlab script file solves the nonlinear Schrodinger equations 9pi{)PDJ  
    %  for 3 cores nonlinear coupler. The output plot is shown in Fig.2 of  0zr%8Q(Q  
    %  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 S_*Gv O  
    _nzTd\L88  
    C=1;                           !iHC++D  
    M1=120,                       % integer for amplitude kDJqT  
    M3=5000;                      % integer for length of coupler Mx0~^l  
    N = 512;                      % Number of Fourier modes (Time domain sampling points) l`6.(6  
    dz =3.14159/(sqrt(2.)*C)/M3;  % length of coupler is divided into M3 segments,  make sure nonlinearity<0.05. ~f[;(?39xZ  
    T =40;                        % length of time:T*T0. 3J8>r|u;1'  
    dt = T/N;                     % time step ,| 8aDL?  
    n = [-N/2:1:N/2-1]';          % Index FW2x  
    t = n.*dt;   ]ZR` 6|"VO  
    ww = 4*n.*n*pi*pi/T/T;        % Square of frequency. Note i^2=-1. r1.zURY  
    w=2*pi*n./T; v:!TqfI  
    g1=-i*ww./2; V]]!0ugvk(  
    g2=-i*ww./2;                  % w=2*pi*f*n./N, f=1/dt=N/T,so w=2*pi*n./TP=0; Nz"K`C>/  
    g3=-i*ww./2; z<P?p  
    P1=0; r4K_Wp  
    P2=0; %Y/;jC Y  
    P3=1; [T'[7 Z  
    P=0; 1QhQ#`$<1  
    for m1=1:M1                 [Djx@x  
    p=0.032*m1;                %input amplitude >^W6'Q$P<  
    s10=p.*sech(p.*t);         %input soliton pulse in waveguide 1 TWRnty-C  
    s1=s10; n<)A5UB5-  
    s20=0.*s10;                %input in waveguide 2 FP y}Wc*UA  
    s30=0.*s10;                %input in waveguide 3 GM8>u O  
    s2=s20; M d Eds|D  
    s3=s30; LH`$<p2''r  
    p10=dt*(sum(abs(s10').*abs(s10'))-0.5*(abs(s10(N,1)*s10(N,1))+abs(s10(1,1)*s10(1,1))));   ETX>wZ  
    %energy in waveguide 1 O\oRM2^u}  
    p20=dt*(sum(abs(s20').*abs(s20'))-0.5*(abs(s20(N,1)*s20(N,1))+abs(s20(1,1)*s20(1,1))));   $zhvI*0  
    %energy in waveguide 2 y_Gs_xg  
    p30=dt*(sum(abs(s30').*abs(s30'))-0.5*(abs(s30(N,1)*s30(N,1))+abs(s30(1,1)*s30(1,1))));   8.%wnH  
    %energy in waveguide 3 7On.y*  
    for m3 = 1:1:M3                                    % Start space evolution :|&6x!  
       s1 = exp(dz*i*(abs(s1).*abs(s1))).*s1;          % 1st step, Solve nonlinear part of NLS U![$7k>,pr  
       s2 = exp(dz*i*(abs(s2).*abs(s2))).*s2; 247vU1  
       s3 = exp(dz*i*(abs(s3).*abs(s3))).*s3; gs.+|4dv  
       sca1 = fftshift(fft(s1));                       % Take Fourier transform xHx_! )7  
       sca2 = fftshift(fft(s2)); %PPy0RZ^  
       sca3 = fftshift(fft(s3)); 7N5M=f.DS(  
       sc1=exp(g1.*dz).*(sca1+i*C*sca2.*dz);           % 2nd step, frequency domain phase shift   a3:45[SO4e  
       sc2=exp(g2.*dz).*(sca2+i*C*(sca1+sca3).*dz); 4QPHT#eqX  
       sc3=exp(g3.*dz).*(sca3+i*C*sca2.*dz); } nIYNeP?D  
       s3 = ifft(fftshift(sc3)); aWvC-vZk  
       s2 = ifft(fftshift(sc2));                       % Return to physical space @^# 9N!Fj]  
       s1 = ifft(fftshift(sc1)); VWYNq^<AT  
    end a>6M{C@pd  
       p1=dt*(sum(abs(s1').*abs(s1'))-0.5*(abs(s1(N,1)*s1(N,1))+abs(s1(1,1)*s1(1,1)))); TR `C|TV>  
       p2=dt*(sum(abs(s2').*abs(s2'))-0.5*(abs(s2(N,1)*s2(N,1))+abs(s2(1,1)*s2(1,1)))); QYj 4D  
       p3=dt*(sum(abs(s3').*abs(s3'))-0.5*(abs(s3(N,1)*s3(N,1))+abs(s3(1,1)*s3(1,1)))); ;$]a.9 -  
       P1=[P1 p1/p10]; VD!PF'  
       P2=[P2 p2/p10]; ]$.w I~J%  
       P3=[P3 p3/p10]; |Ul4n@+2  
       P=[P p*p]; ::GW  
    end 9N2.:<so  
    figure(1) KB^GC5L>  
    plot(P,P1, P,P2, P,P3); T gLr4Ex  
    1j}e2H  
    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~!~