DefaultDiffraction(dz,KX,X,u,U)

%DefaultDiffraction Default diffraction operator for gaffe.
%    Assuming we are solving the 2D NLSE this applies the diffraction
%    operator for paraxial propagation over a (normalised) distance dz.
%
%See also: DefaultDiffraction DefaultDispersion
%          DefaultIdentity DefaultKerr DefaultSelfSteepening,
%          GAFFE_DEMO_SELF, GAFFE_DEMO_GAUSSIAN

% $Author: graceej $ $Date: 2009/10/24 11:08:03 $
% $Revision: 1.4 $

% Copyright (c) 2009, Edward J. Grace
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function L = DefaultDiffraction(dz,KX,X,u,U)
    L = exp((-i*dz*0.25).*(KX{1}.^2+KX{2}.^2)); 
end