Monopole operators in U(1) Chern-Simons-matter theories

We study monopole operators at the infrared fixed points of U(1) ChernSimons-matter theories (QED(3), scalar QED(3), N = 1 SQED(3), and N = 2 SQED(3)) with N matter flavors and Chern-Simons level k. We work in the limit where both N and k are taken to be large with kappa = k/N fixed. In this limit, we extract information about the low-lying spectrum of monopole operators from evaluating the S-2 x S-1 partition function in the sector where the S-2 is threaded by magnetic flux 4 pi q. At leading order in N, we find a large number of monopole operators with equal scaling dimensions and a wide range of spins and flavor symmetry irreducible representations. In two simple cases, we deduce how the degeneracy in the scaling dimensions is broken by the 1/N corrections. For QED(3) at kappa = 0, we provide conformal bootstrap evidence that this near-degeneracy is in fact maintained to small values of N. For N = 2 SQED(3), we find that the lowest dimension monopole operator is generically non-BPS.