Strong versus weak coupling confinement in N=2 supersymmetric QCD

We consider N=2 supersymmetric QCD with the gauge group SU(Nc)=SU(N+1) and Nf number of quark matter multiplets, being perturbed by a small mass term for the adjoint matter, so that its Coulomb branch shrinks to a number of isolated vacua. We discuss the vacuum where r=N quarks develop VEV's for Nf⩾2N=2Nc−2 (in particular, we focus on the Nf=2N and Nf=2N+1 cases). In the equal quark mass limit at large masses this vacuum stays at weak coupling, the low-energy theory has U(N) gauge symmetry and one observes the non-Abelian confinement of monopoles. As we reduce the average quark mass and enter the strong coupling regime the quark condensate transforms into the condensate of dyons. We show that the low energy description in the strongly-coupled domain for the original theory is given by U(N) dual gauge theory of Nf⩾2N light non-Abelian dyons, where the condensed dyons still cause the confinement of monopoles, and not of the quarks, as can be thought by naive duality.