  Using flow equations, we derive an effective quark-quark interaction and
obtain the coupled set of gap equations for the condensates of the CFL phase of
massless N_f=3 dense QCD. We find two different sources of the infrared cutoff
in magnetic interaction. When the penetration depth of the magnetic field
inside the superconductor is less than the coherence length of quark-quark
bound state, our results for the gap agree with those of Son. In the other
case, we obtain parametric enhancement of the gap on the coupling constant.
