Sublattice-symmetric spin-wave theory for the Heisenberg antiferromagnet

We apply the sublattice-symmetric spin-wave theory (SSSW) for Heisenberg antiferromagnets to obtain excited states at zero temperature. We identify a set of spin-wave states that have the correct total spin and correspond to the states with lowest energy in a given sector where $S_z$, the z component of the total spin, is fixed. This approximation gives results in good agreement with the results of exact diagonalization. We also discuss results of SSSW for finite-temperature and dynamical correlations. We recover the same equations as those obtained in the mean-field Schwinger boson theory of Arovas and Auerbach, except for a factor of 3/2. From comparison with exact results obtained by exact diagonalization, we assess the accuracy of the theory when the temperature is finite.