Second harmonic generation study of the antiferromagnetic NiO(001) surface

We report a second harmonic generation (SHG) investigation of the compensated antiferromagnetic NiO(001) surface. We show that bulk and surface contributions to the total SHG signal can be distinguished based on their symmetry properties and spectral dependence. We observed that the coupling of antiferromagnetic order with crystalline structure via crystal distortion effects gives rise to a clearly observable SHG signal of magnetic origin.