Nonabelian superconductors:: vortices and confinement in N=2 SQCD

We study nonabelian vortices (flux tubes) in SU(N) gauge theories, which are responsible for the confinement of (nonabelian) magnetic monopoles. In particular a detailed analysis is given of N = 2 SQCD with gauge group SU(3) deformed by a small adjoint chiral multiplet mass. Tuning the bare quark masses (which we take to be large) to a common value m, we consider a particular vacuum of this theory in which an SU(2) subgroup of the gauge group remains unbroken. We consider 5 greater than or equal to N-f greater than or equal to 4 flavors so that the SU(2) sub-sector remains non asymptotically free: the vortices carrying nonabelian fluxes may be reliably studied in a semi-classical regime. We show that the vortices indeed acquire exact zero modes which generate global rotations of the flux in an SU(2)(C+F) group. We study an effective world sheet theory of these orientational zero modes which reduces to an N = 2 O(3) sigma model in 1 + 1 dimensions. Mirror symmetry then teaches us that the dual SU(2) group is not dynamically broken. (C) 2003 Elsevier B.V. All rights reserved.