Antiferromagnetic Stark-effect in the
(a)(red)-responce to an electric field: component of the transmitted microwave signal detected on the frequency of the AC electric field vs. magnetic field
(b)(blue)-transmitted microwave power vs. magnetic field
The antiferromagnetic Stark effect was found in an antiferromagnet Gd2CuO4. It is the shift of the antiferromagnetic resonance frequency under electric field. Stark- effect in an antiferromagnet is a linear in electric field strength effect due to the linear magnetoelectric effect which is known for antiferromagnets of certain symmetry types. The figure demonstrates the influence of the electric field on the magnetic resonance in the experiment with an AC-electric field which modulates the eigenfrequency of the antiferromagnetic resonance and results in the field dependence of the absorption in form of a derivative of the resonance line.