2026/07/21 by Ryo Hamachika, Takahiro Nishinaka, Shou Tanigawa +1
#hep-th
In recent years, a variety of three-dimensional (3d) N=2 Chern--Simons (CS) matter theories have been constructed that flow to 3d N=4 superconformal field theories (SCFTs) obtained from R-twisted reductions of four-dimensional (4d) N=2 SCFTs. In all previously studied examples, the resulting 3d N=4 SCFTs have trivial Coulomb branches. In this paper, we construct a 3d N=2 CS matter theory that flows to the R-twisted reduction of the (A2,D4) Argyres--Douglas theory. This gives the first example in this class whose infrared 3d N=4 SCFT has a non-trivial Coulomb branch, which we argue is given by the orbifold ℂ2/ℤ2, while its Higgs branch is trivial. We further identify the 4d U(1) R-charge as a mixing of a 3d R-charge with an emergent 3d Coulomb branch flavor charge that has no 4d origin.