Magnetic, dielectric and magnetoelectric properties of polycrystalline Nb2Co4O9

We have investigated the coupling effect between magnetic and electric orders of the commensurate antiferromagnetic compound Nb2Co4O9. In magnetically ordered state (TN = 27.5 K), a significant magnetoelectric effect, in which the electric polarization generated below its antiferromagnetic temperature shows a field-dependent increase, has been observed. Accordingly, the field-induced dielectric peak increases with the increasing applied magnetic field as well. In this manuscript, driving mechanisms of the spin-correlated dielectric anomalies and electric polarization in this compound have been discussed.