Density dependence of quark masses and stability of color-flavor locked phases

Considering the density dependence of quark masses, we investigate the color-flavor-locked matter and its stability relative to (unpaired) strange quark matter. We find that, when the current mass of strange quark ms is small, the strange quark matter remains stable for moderate baryon densities. When ms is large, the gapless phase of the color-flavor-locked matter is found to be difficult to be stable. A schematic phase diagram of three-flavor quark matter is presented, in which the color-flavor-locked phase region is suppressed in comparison with the previous results