Chromomagnetic catalysis of color superconductivity

The effect of an external chromomagnetic field on the phase structure of the extended Nambu–Jona-Lasinio model with two quark flavors is examined. It is shown that, depending on the relationship between the quark coupling constants in the $\bar qq$ and $qq$ channels, chromomagnetic fields of certain types induce spontaneous breaking of chiral, color, or both symmetries simultaneously.