Mixed phases of color superconducting quark matter

We examine electrically and color neutral quark matter in beta-equilibrium focusing on the possibility of mixed phases between different color superconducting phases. To that end we apply the Gibbs criterion to ensure phase equilibrium and discuss the external conditions under which these mixed phases can occur. Neglecting surface and Coulomb effects we find a rich structure of different mixed phases with up to four components, including 2SC and CFL matter as well as more "exotic" components, like a phase with us- and ds-pairing but without ud-pairing. Preliminary estimates indicate, however, that the mixed phases become unstable if surface and Coulomb effects are included. (C) 2002 Elsevier Science B.V. All rights reserved.