Abstract
We study the magnetoelectric coupling in single crystal, in which a part of ions is substituted by nonmagnetic ions. While the antiferromagnetic ordering temperature is gradually suppressed by Ga doping, the magnetocapacitance is enhanced by two orders of magnitude, which we attribute to the lifting of frustration of interlayer spin interactions in doped samples. We also find that the dielectric constant anomaly below magnetic ordering temperature is strongly anisotropic, which we explain using a phenomenological Landau description of ferroelectric antiferromagnets.
- Received 17 October 2006
DOI:https://doi.org/10.1103/PhysRevB.75.174435
©2007 American Physical Society