  The spin-wave excitation spectrum, the magnetization, and the N\'{e}el
temperature for the quasi-two-dimensional spin-1/2 antiferromagnetic Heisenberg
model with compass-model interaction in the plane proposed for iridates are
calculated in the random phase approximation. The spin-wave spectrum agrees
well with data of Lanczos diagonalization. We find that the Neel temperature is
enhanced by the compass-model interaction and is close to the experimental
value for Ba2IrO4.
