The $K^0$ condensed phase of color-flavor locked quark matter : its   formation as a stable state reexamined
  Taking the vector kaon-quark interaction into account, we reexamine in detail the neutral kaon condensation in color-flavor locked quark matter. It is found that the pairing phenomena in the quark matter are somewhat influenced by $K^0$ condensation. Different from the previous predictions, we find that the $K^0$ condensed phase might no longer be more stable than the normal phase even if $K^0$ condensation can occur in the color-flavor locked matter. 
Xiao-Bing Zhang, Xue-Qian Li