% 
% This function represents the equations of motion which generate from
% the potential (3.1) and for gamma_t in equation (2.10).  Two typos in
% the article by Davis and Heller have been corrected.  1.Note that we
% omit the term E_t*t_n in equation (2.10) since it cancels against the
% factor e^{iE_l t} in eq. (2.5).  2. Note also that the last term in eq.
% (2.10) requires a minus sign.  
%
function dydt=fad11(t,y)
omegax=1.1;
omegay=1.0;
lam=-.042;
par=(1.036626+.954787)/2;
%
dydt=[y(2)
     -y(1)*(omegax^2)-2*lam*y(1)*y(3)
      y(4)
     -y(3)*(omegay^2)-lam*y(1)^2
      y(2)^2+y(4)^2-par];
  
  
