We present the results of a self-consistent weak-coupling calculation for the renormalized single-particle properties in an itinerant antiferromagnet. Multiple spin-wave excitations accompany the carrier motion and lead to incoherent contributions to the electronic spectrum. We evaluate the quasiparticle spectral weight and energy dispersoin. In agreement with strong-coupling theories we find the minimum of the dispersion of the quasihole energy to have momentum (±π/2,±π/2) and the dispersion to be flat around the corners of the Brillouin zone. Very good agreement is achieved with available exact diagonalization data.

• Received 14 March 1995

DOI:https://doi.org/10.1103/PhysRevB.52.7395