Large N Chern-Simons-matter fixed points with multiple flavors

A bstract In this paper we analyze the 2 + 1d conformal fixed points arising from SU( N c ) Chern-Simons-matter theories with multiple flavors N f > 1 in the ’t Hooft large N c limit. The multi-flavor generalization of quasi-fermionic theories (fermions or critical scalars coupled to Chern-Simons gauge fields) is straightforward, but this is not true for quasi-bosonic theories (scalars or critical fermions coupled to Chern-Simons gauge fields). The latter theories have three flavor-singlet relevant operators and also three marginal operators, that become exactly marginal for infinite N c , but have a non-zero beta function at order 1 /N c . We compute the beta functions of these couplings in various weak coupling limits, and also discuss their general structure, generalizing previous computations for N f = 1. We find that IR-stable fixed points of the marginal couplings exist for some values of N f and of the ’t Hooft coupling λ , but not for other values, and in one case we can explicitly follow how two pairs of fixed points merge and disappear as λ is increased. We also analyze the “Semi-Critical” conformal field theories that arise when fine-tuning two (rather than three) relevant operators, and compute the beta function for their (single) marginal coupling constant.