Surface operators, dual quivers and contours

Understand

We study half-BPS surface operators in four dimensional N=2 SU(N) gauge theories, and analyze their low-energy effective action on the four dimensional Coulomb branch using equivariant localization.

• We also study surface operators as coupled 2d/4d quiver gauge theories with an SU(N) flavour symmetry.
• In this description, the same surface operator can be described by different quivers that are related to each other by two dimensional Seiberg duality.
• We argue that these dual quivers correspond, on the localization side, to distinct integration contours that can be determined by the Fayet-Iliopoulos parameters of the two dimensional gauge nodes.