1/N expansion for the Schwinger-boson theory of quantum antiferromagnets

We investigate static properties of the two-dimensional quantum Heisenberg antiferromagnet in the framework of the 1/N expansion of the ${\mathit{CP}}^{\mathit{N}\mathrm{-}1}$ model. The calculations are done in the renormalized-classical region. The logarithmic corrections to the spin-correlation length are found to change the temperature dependence of its prefactor. The renormalized staggered susceptibility is completely determined by the renormalization of the spin-correlation length. The results we obtain are in agreement with the renormalization-group and 1/N studies of the O(N) nonlinear σ model.