Mass-deformed N=3 supersymmetric Chern-Simons-matter theory

The maximal extension of supersymmetric Chern-Simons theory coupled to fundamental matter has $\mathcal{N}=3$ supersymmetry. In this short paper, we provide the explicit form of the action for the mass-deformed $\mathcal{N}=3$ supersymmetric $U(N)$ Chern-Simons-matter theory. The theory admits a unique triplet mass-deformation term consistent with supersymmetry. We explicitly construct the mass-deformed $\mathcal{N}=3$ theory in $\mathcal{N}=1$ superspace using a fundamental and an antifundamental superfield.