  The excitation spectrum of a two-component Bose-Einstein condensate has been
discussed by Ref \cite{alex2comp} using the Bogoliubov equations. Here we make
the additional contributions of the linear response function and dielectric
function for a two-component CBG in the condensation phase as well as the
confirmation of the plasmon excitation spectrum using the Gross-Pitaevskii
(G-P) equations.
